Sample records for nasa tla workload

  1. NASA TLA workload analysis support. Volume 3: FFD autopilot scenario validation data

    NASA Technical Reports Server (NTRS)

    Sundstrom, J. L.

    1980-01-01

    The data used to validate a seven time line analysis of forward flight deck autopilot mode for the pilot and copilot for NASA B737 terminal configured vehicle are presented. Demand workloads are given in two forms: workload histograms and workload summaries (bar graphs). A report showing task length and task interaction is also presented.

  2. Timeline Analysis Program (TLA-1)

    NASA Technical Reports Server (NTRS)

    Miller, K. H.

    1976-01-01

    The Timeline Analysis Program (TLA-1) was described. This program is a crew workload analysis computer program that was developed and expanded from previous workload analysis programs, and is designed to be used on the NASA terminal controlled vehicle program. The following information is described: derivation of the input data, processing of the data, and form of the output data. Eight scenarios that were created, programmed, and analyzed as verification of this model were also described.

  3. NASA TLA workload analysis support. Volume 1: Detailed task scenarios for general aviation and metering and spacing studies

    NASA Technical Reports Server (NTRS)

    Sundstrom, J. L.

    1980-01-01

    The techniques required to produce and validate six detailed task timeline scenarios for crew workload studies are described. Specific emphasis is given to: general aviation single pilot instrument flight rules operations in a high density traffic area; fixed path metering and spacing operations; and comparative workload operation between the forward and aft-flight decks of the NASA terminal control vehicle. The validation efforts also provide a cursory examination of the resultant demand workload based on the operating procedures depicted in the detailed task scenarios.

  4. A self-analysis of the NASA-TLX workload measure.

    PubMed

    Noyes, Jan M; Bruneau, Daniel P J

    2007-04-01

    Computer use and, more specifically, the administration of tests and materials online continue to proliferate. A number of subjective, self-report workload measures exist, but the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is probably the most well known and used. The aim of this paper is to consider the workload costs associated with the computer-based and paper versions of the NASA-TLX measure. It was found that there is a significant difference between the workload scores for the two media, with the computer version of the NASA-TLX incurring more workload. This has implications for the practical use of the NASA-TLX as well as for other computer-based workload measures.

  5. NASA TLA workload analysis support. Volume 2: Metering and spacing studies validation data

    NASA Technical Reports Server (NTRS)

    Sundstrom, J. L.

    1980-01-01

    Four sets of graphic reports--one for each of the metering and spacing scenarios--are presented. The complete data file from which the reports were generated is also given. The data was used to validate the detail task of both the pilot and copilot for four metering and spacing scenarios. The output presents two measures of demand workload and a report showing task length and task interaction.

  6. NASA TLX: software for assessing subjective mental workload.

    PubMed

    Cao, Alex; Chintamani, Keshav K; Pandya, Abhilash K; Ellis, R Darin

    2009-02-01

    The NASA Task Load Index (TLX) is a popular technique for measuring subjective mental workload. It relies on a multidimensional construct to derive an overall workload score based on a weighted average of ratings on six subscales: mental demand, physical demand, temporal demand, performance, effort, and frustration level. A program for implementing a computerized version of the NASA TLX is described. The software version assists in simplifying collection, postprocessing, and storage of raw data. The program collects raw data from the subject and calculates the weighted (or unweighted) workload score, which is output to a text file. The program can also be tailored to a specific experiment using a simple input text file, if desired. The program was designed in Visual Studio 2005 and is capable of running on a Pocket PC with Windows CE or on a PC with Windows 2000 or higher. The NASA TLX program is available for free download.

  7. Timeline analysis program (TLA-1), appendices

    NASA Technical Reports Server (NTRS)

    Miller, K. H.

    1976-01-01

    Appendices for the Timeline Analysis Program (TLA-1) were given. The appendices contain the Atlanta terminal area scenarios, the task catalog and the control and display configurations for the forward and aft flight decks of the NASA 515 aircraft, and the event/procedure, phase, mission, and subsystem catalogs.

  8. Mental workload measurement in operator control room using NASA-TLX

    NASA Astrophysics Data System (ADS)

    Sugarindra, M.; Suryoputro, M. R.; Permana, A. I.

    2017-12-01

    The workload, encountered a combination of physical workload and mental workload, is a consequence of the activities for workers. Central control room is one department in the oil processing company, employees tasked with monitoring the processing unit for 24 hours nonstop with a combination of 3 shifts in 8 hours. NASA-TLX (NASA Task Load Index) is one of the subjective mental workload measurement using six factors, namely the Mental demand (MD), Physical demand (PD), Temporal demand (TD), Performance (OP), Effort (EF), frustration levels (FR). Measurement of a subjective mental workload most widely used because it has a high degree of validity. Based on the calculation of the mental workload, there at 5 units (DTU, NPU, HTU, DIST and OPS) at the control chamber (94; 83.33; 94.67; 81, 33 and 94.67 respectively) that categorize as very high mental workload. The high level of mental workload on the operator in the Central Control Room is a requirement to have high accuracy, alertness and can make decisions quickly

  9. Using the NASA Task Load Index to Assess Workload in Electronic Medical Records.

    PubMed

    Hudson, Darren; Kushniruk, Andre W; Borycki, Elizabeth M

    2015-01-01

    Electronic medical records (EMRs) has been expected to decrease health professional workload. The NASA Task Load Index has become an important tool for assessing workload in many domains. However, its application in assessing the impact of an EMR on nurse's workload has remained to be explored. In this paper we report the results of a study of workload and we explore the utility of applying the NASA Task Load Index to assess impact of an EMR at the end of its lifecycle on nurses' workload. It was found that mental and temporal demands were the most responsible for the workload. Further work along these lines is recommended.

  10. Workload assessment of surgeons: correlation between NASA TLX and blinks.

    PubMed

    Zheng, Bin; Jiang, Xianta; Tien, Geoffrey; Meneghetti, Adam; Panton, O Neely M; Atkins, M Stella

    2012-10-01

    Blinks are known as an indicator of visual attention and mental stress. In this study, surgeons' mental workload was evaluated utilizing a paper assessment instrument (National Aeronautics and Space Administration Task Load Index, NASA TLX) and by examining their eye blinks. Correlation between these two assessments was reported. Surgeons' eye motions were video-recorded using a head-mounted eye-tracker while the surgeons performed a laparoscopic procedure on a virtual reality trainer. Blink frequency and duration were computed using computer vision technology. The level of workload experienced during the procedure was reported by surgeons using the NASA TLX. A total of 42 valid videos were recorded from 23 surgeons. After blinks were computed, videos were divided into two groups based on the blink frequency: infrequent group (≤ 6 blinks/min) and frequent group (more than 6 blinks/min). Surgical performance (measured by task time and trajectories of tool tips) was not significantly different between these two groups, but NASA TLX scores were significantly different. Surgeons who blinked infrequently reported a higher level of frustration (46 vs. 34, P = 0.047) and higher overall level of workload (57 vs. 47, P = 0.045) than those who blinked more frequently. The correlation coefficients (Pearson test) between NASA TLX and the blink frequency and duration were -0.17 and 0.446. Reduction of blink frequency and shorter blink duration matched the increasing level of mental workload reported by surgeons. The value of using eye-tracking technology for assessment of surgeon mental workload was shown.

  11. TLA+: Whence, Wherefore, and Whither

    NASA Technical Reports Server (NTRS)

    Lamport, Leslie

    2009-01-01

    The evolution of my ideas on specification and verification, and how they led to the TLA+ specification language. What is good and bad about TLA+. A brief description of the next version of TLA+ and its tools. E.

  12. Higher mental workload is associated with poorer laparoscopic performance as measured by the NASA-TLX tool.

    PubMed

    Yurko, Yuliya Y; Scerbo, Mark W; Prabhu, Ajita S; Acker, Christina E; Stefanidis, Dimitrios

    2010-10-01

    Increased workload during task performance may increase fatigue and facilitate errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a previously validated tool for workload self-assessment. We assessed the relationship of workload and performance during simulator training on a complex laparoscopic task. NASA-TLX workload data from three separate trials were analyzed. All participants were novices (n = 28), followed the same curriculum on the fundamentals of laparoscopic surgery suturing model, and were tested in the animal operating room (OR) on a Nissen fundoplication model after training. Performance and workload scores were recorded at baseline, after proficiency achievement, and during the test. Performance, NASA-TLX scores, and inadvertent injuries during the test were analyzed and compared. Workload scores declined during training and mirrored performance changes. NASA-TLX scores correlated significantly with performance scores (r = -0.5, P < 0.001). Participants with higher workload scores caused more inadvertent injuries to adjacent structures in the OR (r = 0.38, P < 0.05). Increased mental and physical workload scores at baseline correlated with higher workload scores in the OR (r = 0.52-0.82; P < 0.05) and more inadvertent injuries (r = 0.52, P < 0.01). Increased workload is associated with inferior task performance and higher likelihood of errors. The NASA-TLX questionnaire accurately reflects workload changes during simulator training and may identify individuals more likely to experience high workload and more prone to errors during skill transfer to the clinical environment.

  13. Viewing the workload of vigilance through the lenses of the NASA-TLX and the MRQ.

    PubMed

    Finomore, Victor S; Shaw, Tyler H; Warm, Joel S; Matthews, Gerald; Boles, David B

    2013-12-01

    The aim of this study was to compare the effectiveness of a new index of perceived mental workload, the Multiple Resource Questionnaire (MRQ), with the standard measure of workload used in the study of vigilance, the NASA Task Load Index (NASA-TLX). The NASA-TLX has been used extensively to demonstrate that vigilance tasks impose a high level of workload on observers. However, this instrument does not specify the information-processing resources needed for task performance. The MRQ offers a tool to measure the workload associated with vigilance assignments in which such resources can be identified. Two experiments were performed in which factors known to influence task demand were varied. Included were the detection of stimulus presence or absence, detecting critical signals by means of successive-type (absolute judgment) and simultaneous-type (comparative judgment) discriminations, and operating under multitask vs. single-task conditions. The MRQ paralleled the NASA-TLX in showing that vigilance tasks generally induce high levels of workload and that workload scores are greater in detecting stimulus absence than presence and in making successive as compared to simultaneous-type discriminations. Additionally, the MRQ was more effective than the NASA-TLX in reflecting higher workload in the context of multitask than in single-task conditions. The resource profiles obtained with MRQ fit well with the nature of the vigilance tasks employed, testifying to the scale's content validity. The MRQ may be a meaningful addition to the NASA-TLX for measuring the workload of vigilance assignments. By uncovering knowledge representation associated with different tasks, the MRQ may aid in designing operational vigilance displays.

  14. MEASURING WORKLOAD OF ICU NURSES WITH A QUESTIONNAIRE SURVEY: THE NASA TASK LOAD INDEX (TLX).

    PubMed

    Hoonakker, Peter; Carayon, Pascale; Gurses, Ayse; Brown, Roger; McGuire, Kerry; Khunlertkit, Adjhaporn; Walker, James M

    2011-01-01

    High workload of nurses in Intensive Care Units (ICUs) has been identified as a major patient safety and worker stress problem. However, relative little attention has been dedicated to the measurement of workload in healthcare. The objectives of this study are to describe and examine several methods to measure workload of ICU nurses. We then focus on the measurement of ICU nurses' workload using a subjective rating instrument: the NASA TLX.We conducted secondary data analysis on data from two, multi-side, cross-sectional questionnaire studies to examine several instruments to measure ICU nurses' workload. The combined database contains the data from 757 ICU nurses in 8 hospitals and 21 ICUs.Results show that the different methods to measure workload of ICU nurses, such as patient-based and operator-based workload, are only moderately correlated, or not correlated at all. Results show further that among the operator-based instruments, the NASA TLX is the most reliable and valid questionnaire to measure workload and that NASA TLX can be used in a healthcare setting. Managers of hospitals and ICUs can benefit from the results of this research as it provides benchmark data on workload experienced by nurses in a variety of ICUs.

  15. MEASURING WORKLOAD OF ICU NURSES WITH A QUESTIONNAIRE SURVEY: THE NASA TASK LOAD INDEX (TLX)

    PubMed Central

    Hoonakker, Peter; Carayon, Pascale; Gurses, Ayse; Brown, Roger; McGuire, Kerry; Khunlertkit, Adjhaporn; Walker, James M.

    2012-01-01

    High workload of nurses in Intensive Care Units (ICUs) has been identified as a major patient safety and worker stress problem. However, relative little attention has been dedicated to the measurement of workload in healthcare. The objectives of this study are to describe and examine several methods to measure workload of ICU nurses. We then focus on the measurement of ICU nurses’ workload using a subjective rating instrument: the NASA TLX. We conducted secondary data analysis on data from two, multi-side, cross-sectional questionnaire studies to examine several instruments to measure ICU nurses’ workload. The combined database contains the data from 757 ICU nurses in 8 hospitals and 21 ICUs. Results show that the different methods to measure workload of ICU nurses, such as patient-based and operator-based workload, are only moderately correlated, or not correlated at all. Results show further that among the operator-based instruments, the NASA TLX is the most reliable and valid questionnaire to measure workload and that NASA TLX can be used in a healthcare setting. Managers of hospitals and ICUs can benefit from the results of this research as it provides benchmark data on workload experienced by nurses in a variety of ICUs. PMID:22773941

  16. Assessment of workload using NASA Task Load Index in perianesthesia nursing.

    PubMed

    Young, Gloria; Zavelina, Lyubov; Hooper, Vallire

    2008-04-01

    According to the Institute of Medicine (IOM), as many as 44,000 to 98,000 people in the United States die in hospitals every year due to medical errors. Multiple physiological and psychological factors can impact the health care provider's attention span, making medical errors more likely. Some of these factors include increased workload, fatigue, cognitive overload, ineffective interpersonal communications, and faulty information processing. Postanesthesia nurses, responsible for providing care to unstable patients emerging from anesthesia with multiple life-threatening conditions, must make critical decisions on a minute-by-minute basis. The current ASPAN Patient Classification/Recommended Staffing Guidelines does not adequately take into account varying care requirements among the patients. If a tool could be found that effectively evaluated staff's workload, ongoing assessment would be enhanced and resources better used. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX), a multifaceted tool for evaluating perceptual (subjective) workload, has seen extensive applications and is widely regarded as the strongest tool available for reporting perceptions of workload. This article will survey various uses of the NASA-TLX and consider the potential uses for this tool in perianesthesia nursing.

  17. The NASA Task Load Index as a measure of overall workload among neonatal, paediatric and adult intensive care nurses.

    PubMed

    Tubbs-Cooley, Heather L; Mara, Constance A; Carle, Adam C; Gurses, Ayse P

    2018-02-12

    The NASA Task Load Index (NASA-TLX) is a subjective workload assessment scale developed for use in aviation and increasingly applied to healthcare. The scale purports to measure overall workload as a single variable calculated by summing responses to six items. Since no data address the validity of this scoring approach in health care, we evaluated the single factor structure of the NASA-TLX as a measure of overall workload among intenisive care nurses. Confirmatory factor analysis of data from two studies of nurse workload in neonatal, paediatric, and adult intensive care units. Study 1 data were obtained from 136 nurses in one neonatal intensive care unit. Study 2 data were collected from 300 nurses in 17 adult, paediatric and neonatal units. Nurses rated their workload using the NASA-TLX's paper version. A single factor model testing whether all six items measured a single overall workload variable fit least well (RMSEA = 0.14; CFI = 0.91; TLI = 0.85). A second model that specified two items as outcomes of overall workload had acceptable fit (RMSEA = 0.08; CFI = 0.97; TLI = 0.95) while a third model of four items fit best (RMSEA = 0.06; CFI > 0.99; TLI = 0.99). A summed score from four of six NASA-TLX items appears to most reliably measure a single overall workload variable among intensive care nurses. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. NASA-Ames workload research program

    NASA Technical Reports Server (NTRS)

    Hart, Sandra

    1988-01-01

    Research has been underway for several years to develop valid and reliable measures and predictors of workload as a function of operator state, task requirements, and system resources. Although the initial focus of this research was on aeronautics, the underlying principles and methodologies are equally applicable to space, and provide a set of tools that NASA and its contractors can use to evaluate design alternatives from the perspective of the astronauts. Objectives and approach of the research program are described, as well as the resources used in conducting research and the conceptual framework around which the program evolved. Next, standardized tasks are described, in addition to predictive models and assessment techniques and their application to the space program. Finally, some of the operational applications of these tasks and measures are reviewed.

  19. Sensitivity and diagnosticity of NASA-TLX and simplified SWAT to assess the mental workload associated with operating an agricultural sprayer.

    PubMed

    Dey, Asit; Mann, Danny D

    2010-07-01

    The objectives of the present study were: a) to investigate three continuous variants of the NASA-Task Load Index (TLX) (standard NASA (CNASA), average NASA (C1NASA) and principal component NASA (PCNASA)) and five different variants of the simplified subjective workload assessment technique (SSWAT) (continuous standard SSWAT (CSSWAT), continuous average SSWAT (C1SSWAT), continuous principal component SSWAT (PCSSWAT), discrete event-based SSWAT (D1SSWAT) and discrete standard SSWAT (DSSWAT)) in terms of their sensitivity and diagnosticity to assess the mental workload associated with agricultural spraying; b) to compare and select the best variants of NASA-TLX and SSWAT for future mental workload research in the agricultural domain. A total of 16 male university students (mean 30.4 +/- 12.5 years) participated in this study. All the participants were trained to drive an agricultural spraying simulator. Sensitivity was assessed by the ability of the scales to report the maximum change in workload ratings due to the change in illumination and difficulty levels. In addition, the factor loading method was used to quantify sensitivity. The diagnosticity was assessed by the ability of the scale to diagnose the change in task levels from single to dual. Among all the variants of NASA-TLX and SSWAT, PCNASA and discrete variants of SSWAT showed the highest sensitivity and diagnosticity. Moreover, among all the variants of NASA and SSWAT, the discrete variants of SSWAT showed the highest sensitivity and diagnosticity but also high between-subject variability. The continuous variants of both scales had relatively low sensitivity and diagnosticity and also low between-subject variability. Hence, when selecting a scale for future mental workload research in the agricultural domain, a researcher should decide what to compromise: 1) between-subject variability or 2) sensitivity and diagnosticity. STATEMENT OF RELEVANCE: The use of subjective workload scales is very popular in

  20. Flight Crew Workload Evaluation Based on the Workload Function Distribution Method.

    PubMed

    Zheng, Yiyuan; Lu, Yanyu; Jie, Yuwen; Fu, Shan

    2017-05-01

    The minimum flight crew on the flight deck should be established according to the workload for individual crewmembers. Typical workload measures consist of three types: subjective rating scale, task performance, and psychophysiological measures. However, all these measures have their own limitations. To reflect flight crew workload more specifically and comprehensively within the flight environment, and more directly comply with airworthiness regulations, the Workload Function Distribution Method, which combined the basic six workload functions, was proposed. The analysis was based on the different conditions of workload function numbers. Each condition was analyzed from two aspects, which were overall proportion and effective proportion. Three types of approach tasks were used in this study and the NASA-TLX scale was implemented for comparison. Neither the one-function condition nor the two-function condition had the same results with NASA-TLX. However, both the three-function and the four- to six- function conditions were identical with NASA-TLX. Further, the significant differences were different on four to six conditions. The overall proportion was insignificant, while the effective proportions were significant. The results show that the conditions with one function and two functions seemed to have no influence on workload, while executing three functions and four to six functions had an impact on workload. Besides, effective proportions of workload functions were more precisely compared with the overall proportions to indicate workload, especially in the conditions with multiple functions.Zheng Y, Lu Y, Jie Y, Fu S. Flight crew workload evaluation based on the workload function distribution method. Aerosp Med Hum Perform. 2017; 88(5):481-486.

  1. TLA-2, a Novel Ambler Class A Expanded-Spectrum β-Lactamase

    PubMed Central

    Girlich, Delphine; Poirel, Laurent; Schlüter, Andreas; Nordmann, Patrice

    2005-01-01

    β-Lactamase TLA-2 is encoded by a 47-kb plasmid isolated from an unidentified bacterial strain from a wastewater treatment plant. TLA-2 is an Ambler class A β-lactamase that shares 52% amino acid identity with CGA-1 from Chryseobacterium gleum and 51% with TLA-1 from Escherichia coli. The enzyme hydrolyzes mostly cephalosporins. PMID:16251326

  2. TLA-2, a novel Ambler class A expanded-spectrum beta-lactamase.

    PubMed

    Girlich, Delphine; Poirel, Laurent; Schlüter, Andreas; Nordmann, Patrice

    2005-11-01

    Beta-lactamase TLA-2 is encoded by a 47-kb plasmid isolated from an unidentified bacterial strain from a wastewater treatment plant. TLA-2 is an Ambler class A beta-lactamase that shares 52% amino acid identity with CGA-1 from Chryseobacterium gleum and 51% with TLA-1 from Escherichia coli. The enzyme hydrolyzes mostly cephalosporins.

  3. Measuring mental workload with the NASA-TLX needs to examine each dimension rather than relying on the global score: an example with driving.

    PubMed

    Galy, Edith; Paxion, Julie; Berthelon, Catherine

    2018-04-01

    The distinction between several components of mental workload is often made in the ergonomics literature. However, measurements used are often established from a global score, notably with several questionnaires that originally reflect several dimensions. The present study tested the effect of driving situation complexity, experience and subjective levels of tension and alertness on each dimension of the NASA-TLX questionnaire of workload, in order to highlight the potential influence of intrinsic, extraneous and germane load factors. The results showed that, in complex situation, mental, temporal and physical demand (load dimensions) increased, and that novice drivers presented high physical demand when subjective tension was low on performance. Moreover, increase of mental and physical demand increased effort. It thus, appears essential to distinguish the different components of mental workload used in the NASA-TLX questionnaire. Practitioner Summary: Currently, global score of NASA-TLX questionnaire is used to measure mental workload. Here, we considered independently each dimension of NASA-TLX, and results showed that mental load factors (driving situation complexity, experience, subjective tension and alertness) had a different effect on dimensions, questioning global score use to evaluate workload.

  4. Validation of the NASA-TLX Score in Ongoing Assessment of Mental Workload During a Laparoscopic Learning Curve in Bariatric Surgery.

    PubMed

    Ruiz-Rabelo, Juan Francisco; Navarro-Rodriguez, Elena; Di-Stasi, Leandro Luigi; Diaz-Jimenez, Nelida; Cabrera-Bermon, Juan; Diaz-Iglesias, Carlos; Gomez-Alvarez, Manuel; Briceño-Delgado, Javier

    2015-12-01

    Fatigue and mental workload are directly associated with high-complexity tasks. In general, difficult tasks produce a higher mental workload, leaving little opportunity to deal with new/unexpected events and increasing the likelihood of performance errors. The laparoscopic Roux-en-Y gastric bypass (LRYGB) learning curve is considered to be one of the most difficult to complete in laparoscopic surgery. We wished to validate the National Aeronautics and Space Administration Task Load Index (NASA-TLX) in LRYGB and identify factors that could provoke a higher mental workload for surgeons during the learning curve. A single surgeon was enrolled to undertake 70 consecutive LRYGB procedures with two internal surgeons mentoring the first 35 cases. Patients were consecutive and ranked from case 35 to case 105 according to the date of the surgical procedure ("case rank"). Self-ratings of satisfaction, performance, and fatigue were measured at the end of surgery using a validated NASA-TLX questionnaire. The procedure was recorded for later viewing by two external evaluators. General data for patients and surgical variables were collected prospectively. A moderate correlation between the NASA-TLX score, BMI, operative time, and volumes of blood drainage was observed. There was no correlation between the NASA-TLX score and duration of hospital stay or time of drain removal. BMI ≥50 kg/m(2), male sex, inexperienced first assistant, and type 2 diabetes mellitus were identified as independent predictive factors of a higher NASA-TLX score. The NASA-TLX is a valid tool to gauge mental workload in LRYGB.

  5. Effect of Toxoplasma lysate antigen (TLA) on feline cytotoxicity against FeLV positive lymphoma cells.

    PubMed

    Yang, M P; Goitsuka, R; Ono, K; Suzuki, N; Hasegawa, A

    1990-08-01

    The cytotoxic activities of feline spleen cells treated with Toxoplasma lysate antigen (TLA) were assayed against feline leukemia virus (FeLV)-producing lymphoma. FL74 cells, and xenogeneic target lymphoma, mouse YAC-1 cells. The TLA treatments were performed in vivo alone, in vitro alone, and in vivo plus in vitro, respectively. In vivo plus in vitro treatments with TLA induced a marked augmentation in cytotoxic activity of spleen cells to FL74 cells. The treatment with TLA in vivo alone showed an enhancement of cytotoxic activity but in vitro alone did not. The cytotoxic effects of TLA-treated spleen cells obtained from the cats which had been previously immunized with live FL74 cells were similar to those of spleen cells from non-immunized cats treated with TLA. However, no increase of cytotoxicity was shown in the response to mouse YAC-1 cells regardless of TLA treatments. These results indicated that the in vivo TLA treatment augmented the cytotoxicity of feline spleen cells against FeLV-producing lymphoma cell.

  6. Transport pilot workload - A comparison of two subjective techniques

    NASA Technical Reports Server (NTRS)

    Battiste, Vernol; Bortolussi, Michael

    1988-01-01

    Although SWAT and NASA-TLX workload scales have been compared on numerous occasions, they have not been compared in the context of transport operations. Transport pilot workload has traditionally been classified as long periods of low workload with occasional spikes of high workload. Thus, the relative sensitivity of the scales to variations in workload at the low end of the scale were evaluated. This study was a part of a larger study which investigated workload measures for aircraft certification, conducted in a Phase II certified Link/Boeing 727 simulator. No significant main effects were found for any performance-based measures of workload. However, both SWAT and NASA-TLX were sensitive to differences between high and low workload flights and to differences among flight segments. NASA-TLX (but not SWAT) was sensitive to the increase in workload during the cruise segment of the high workload flight. Between-subject variability was high for SWAT. NASA-TLX was found to be stable when compared in the test/retest paradigm. A test/retest by segment interaction suggested that this was not the case for SWAT ratings.

  7. [The appraisal of reliability and validity of subjective workload assessment technique and NASA-task load index].

    PubMed

    Xiao, Yuan-mei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia

    2005-06-01

    To test the reliability and validity of two mental workload assessment scales, i.e. subjective workload assessment technique (SWAT) and NASA task load index (NASA-TLX). One thousand two hundred and sixty-eight mental workers were sampled from various kinds of occupations, such as scientific research, education, administration and medicine, etc, with randomized cluster sampling. The re-test reliability, split-half reliability, Cronbach's alpha coefficient and correlation coefficients between item score and total score were adopted to test the reliability. The test of validity included structure validity. The re-test reliability coefficients of these two scales and their items were ranged from 0.516 to 0.753 (P < 0.01), indicating the two scales had good re-test reliability; the split-half reliability of SWAT was 0.645, and its Cronbach's alpha coefficient was more than 0.80, all the correlation coefficients between its items score and total score were more than 0.70; as for NASA-TLX, both the split-half reliability and Cronbach's alpha coefficient were more than 0.80, the correlation coefficients between its items score and total score were all more than 0.60 (P < 0.01) except the item of performance. Both scales had good inner consistency. The Pearson correlation coefficient between the two scales was 0.492 (P < 0.01), implying the results of the two scales had good consistency. Factor analysis showed that the two scales had good structure validity. Both SWAT and NASA-TLX have good reliability and validity and may be used as a valid tool to assess mental workload in China after being revised properly.

  8. Measuring perceived mental workload in children.

    PubMed

    Laurie-Rose, Cynthia; Frey, Meredith; Ennis, Aristi; Zamary, Amanda

    2014-01-01

    Little is known about the mental workload, or psychological costs, associated with information processing tasks in children. We adapted the highly regarded NASA Task Load Index (NASA-TLX) multidimensional workload scale (Hart & Staveland, 1988) to test its efficacy for use with elementary school children. We developed 2 types of tasks, each with 2 levels of demand, to draw differentially on resources from the separate subscales of workload. In Experiment 1, our participants were both typical and school-labeled gifted children recruited from 4th and 5th grades. Results revealed that task type elicited different workload profiles, and task demand directly affected the children's experience of workload. In general, gifted children experienced less workload than typical children. Objective response time and accuracy measures provide evidence for the criterion validity of the workload ratings. In Experiment 2, we applied the same method with 1st- and 2nd-grade children. Findings from Experiment 2 paralleled those of Experiment 1 and support the use of NASA-TLX with even the youngest elementary school children. These findings contribute to the fledgling field of educational ergonomics and attest to the innovative application of workload research. Such research may optimize instructional techniques and identify children at risk for experiencing overload.

  9. TLA — markers and nuclear scanning method for wear rate monitoring

    NASA Astrophysics Data System (ADS)

    Stan-Sion, C.; Plostinaru, D.; Ivan, A.; Ivanov, E.; Dudu, D.; Catana, M.; Roman, M.

    1994-08-01

    Two new extensions of the TLA-direct measuring method are presented: the TLA-markers for wear control and the nuclear scanning method for monitoring wear non-uniformity on large surfaces. Both methods were applied to measure the material loss on the surface of railway car brake disks.

  10. Mental workload during brain-computer interface training.

    PubMed

    Felton, Elizabeth A; Williams, Justin C; Vanderheiden, Gregg C; Radwin, Robert G

    2012-01-01

    It is not well understood how people perceive the difficulty of performing brain-computer interface (BCI) tasks, which specific aspects of mental workload contribute the most, and whether there is a difference in perceived workload between participants who are able-bodied and disabled. This study evaluated mental workload using the NASA Task Load Index (TLX), a multi-dimensional rating procedure with six subscales: Mental Demands, Physical Demands, Temporal Demands, Performance, Effort, and Frustration. Able-bodied and motor disabled participants completed the survey after performing EEG-based BCI Fitts' law target acquisition and phrase spelling tasks. The NASA-TLX scores were similar for able-bodied and disabled participants. For example, overall workload scores (range 0-100) for 1D horizontal tasks were 48.5 (SD = 17.7) and 46.6 (SD 10.3), respectively. The TLX can be used to inform the design of BCIs that will have greater usability by evaluating subjective workload between BCI tasks, participant groups, and control modalities. Mental workload of brain-computer interfaces (BCI) can be evaluated with the NASA Task Load Index (TLX). The TLX is an effective tool for comparing subjective workload between BCI tasks, participant groups (able-bodied and disabled), and control modalities. The data can inform the design of BCIs that will have greater usability.

  11. Measuring workload in collaborative contexts: trait versus state perspectives.

    PubMed

    Helton, William S; Funke, Gregory J; Knott, Benjamin A

    2014-03-01

    In the present study, we explored the state versus trait aspects of measures of task and team workload in a disaster simulation. There is often a need to assess workload in both individual and collaborative settings. Researchers in this field often use the NASATask Load Index (NASA-TLX) as a global measure of workload by aggregating the NASA-TLX's component items. Using this practice, one may overlook the distinction between traits and states. Fifteen dyadic teams (11 inexperienced, 4 experienced) completed five sessions of a tsunami disaster simulator. After every session, individuals completed a modified version of the NASA-TLX that included team workload measures.We then examined the workload items by using a between-subjects and within-subjects perspective. Between-subjects and within-subjects correlations among the items indicated the workload items are more independent within subjects (as states) than between subjects (as traits). Correlations between the workload items and simulation performance were also different at the trait and state levels. Workload may behave differently at trait (between-subjects) and state (within-subjects) levels. Researchers interested in workload measurement as a state should take a within-subjects perspective in their analyses.

  12. Respiratory sinus arrhythmia as a measure of cognitive workload.

    PubMed

    Muth, Eric R; Moss, Jason D; Rosopa, Patrick J; Salley, James N; Walker, Alexander D

    2012-01-01

    The current standard for measuring cognitive workload is the NASA Task-load Index (TLX) questionnaire. Although this measure has a high degree of reliability, diagnosticity, and sensitivity, a reliable physiological measure of cognitive workload could provide a non-invasive, objective measure of workload that could be tracked in real or near real-time without interrupting the task. This study investigated changes in respiratory sinus arrhythmia (RSA) during seven different sub-sections of a proposed selection test for Navy aviation and compared them to changes reported on the NASA-TLX. 201 healthy participants performed the seven tasks of the Navy's Performance Based Measure. RSA was measured during each task and the NASA-TLX was administered after each task. Multi-level modeling revealed that RSA significantly predicted NASA-TLX scores. A moderate within-subject correlation was also found between RSA and NASA TLX scores. The findings support the potential development of RSA as a real-time measure of cognitive workload. Copyright © 2011. Published by Elsevier B.V.

  13. Fuzzy-TLX: using fuzzy integrals for evaluating human mental workload with NASA-Task Load indeX in laboratory and field studies.

    PubMed

    Mouzé-Amady, Marc; Raufaste, Eric; Prade, Henri; Meyer, Jean-Pierre

    2013-01-01

    The aim of this study was to assess mental workload in which various load sources must be integrated to derive reliable workload estimates. We report a new algorithm for computing weights from qualitative fuzzy integrals and apply it to the National Aeronautics and Space Administration -Task Load indeX (NASA-TLX) subscales in order to replace the standard pair-wise weighting technique (PWT). In this paper, two empirical studies were reported: (1) In a laboratory experiment, age- and task-related variables were investigated in 53 male volunteers and (2) In a field study, task- and job-related variables were studied on aircrews during 48 commercial flights. The results found in this study were as follows: (i) in the experimental setting, fuzzy estimates were highly correlated with classical (using PWT) estimates; (ii) in real work conditions, replacing PWT by automated fuzzy treatments simplified the NASA-TLX completion; (iii) the algorithm for computing fuzzy estimates provides a new classification procedure sensitive to various variables of work environments and (iv) subjective and objective measures can be used for the fuzzy aggregation of NASA-TLX subscales. NASA-TLX, a classical tool for mental workload assessment, is based on a weighted sum of ratings from six subscales. A new algorithm, which impacts on input data collection and computes weights and indexes from qualitative fuzzy integrals, is evaluated through laboratory and field studies. Pros and cons are discussed.

  14. Expression of mouse Tla region class I genes in tissues enriched for gamma delta cells.

    PubMed

    Eghtesady, P; Brorson, K A; Cheroutre, H; Tigelaar, R E; Hood, L; Kronenberg, M

    1992-01-01

    The Tla region of the BALB/c mouse major histocompatibility complex contains at least 20 class I genes. The function of the products of these genes is unknown, but recent evidence demonstrates that some Tla region gene products could be involved in presentation of antigens to gamma delta T cells. We have generated a set of polymerase chain reaction (PCR) oligonucleotide primers and hybridization probes that permit us to specifically amplify and detect expression of 11 of the 20 BALB/c Tla region genes. cDNA prepared from 12 adult and fetal tissues and from seven cell lines was analyzed. In some cases, northern blot analysis or staining with monoclonal antibodies specific for the Tla-encoded thymus leukemia (TL) antigen were used to confirm the expression pattern of several of the genes as determined by PCR. Some Tla region genes, such as T24d and the members of the T10d/T22d gene pair, are expressed in a wide variety of tissues in a manner similar to the class I transplantation antigens. The members of the TL antigen encoding gene pair, T3d/T18d, are expressed in only a limited number of organs, including several sites enriched for gamma delta T cells. Other Tla region genes, including T1d, T2d, T16d, and T17d, are transcriptionally silent and transcripts from the T8d/T20d gene pair do not undergo proper splicing. In general, sites that contain gamma delta T lymphocytes have Tla region transcripts. The newly identified pattern of expression of the genes analyzed in sites containing gamma delta T cells further extends the list of potential candidates for antigen presentation to gamma delta T cells.

  15. Mental Workload during Brain-Computer Interface Training

    PubMed Central

    Felton, Elizabeth A.; Williams, Justin C.; Vanderheiden, Gregg C.; Radwin, Robert G.

    2012-01-01

    It is not well understood how people perceive the difficulty of performing brain-computer interface (BCI) tasks, which specific aspects of mental workload contribute the most, and whether there is a difference in perceived workload between participants who are able-bodied and disabled. This study evaluated mental workload using the NASA Task Load Index (TLX), a multi-dimensional rating procedure with six subscales: Mental Demands, Physical Demands, Temporal Demands, Performance, Effort, and Frustration. Able-bodied and motor disabled participants completed the survey after performing EEG-based BCI Fitts’ law target acquisition and phrase spelling tasks. The NASA-TLX scores were similar for able-bodied and disabled participants. For example, overall workload scores (range 0 – 100) for 1D horizontal tasks were 48.5 (SD = 17.7) and 46.6 (SD 10.3), respectively. The TLX can be used to inform the design of BCIs that will have greater usability by evaluating subjective workload between BCI tasks, participant groups, and control modalities. PMID:22506483

  16. Quantitative assessment of workload and stressors in clinical radiation oncology.

    PubMed

    Mazur, Lukasz M; Mosaly, Prithima R; Jackson, Marianne; Chang, Sha X; Burkhardt, Katharin Deschesne; Adams, Robert D; Jones, Ellen L; Hoyle, Lesley; Xu, Jing; Rockwell, John; Marks, Lawrence B

    2012-08-01

    Workload level and sources of stressors have been implicated as sources of error in multiple settings. We assessed workload levels and sources of stressors among radiation oncology professionals. Furthermore, we explored the potential association between workload and the frequency of reported radiotherapy incidents by the World Health Organization (WHO). Data collection was aimed at various tasks performed by 21 study participants from different radiation oncology professional subgroups (simulation therapists, radiation therapists, physicists, dosimetrists, and physicians). Workload was assessed using National Aeronautics and Space Administration Task-Load Index (NASA TLX). Sources of stressors were quantified using observational methods and segregated using a standard taxonomy. Comparisons between professional subgroups and tasks were made using analysis of variance ANOVA, multivariate ANOVA, and Duncan test. An association between workload levels (NASA TLX) and the frequency of radiotherapy incidents (WHO incidents) was explored (Pearson correlation test). A total of 173 workload assessments were obtained. Overall, simulation therapists had relatively low workloads (NASA TLX range, 30-36), and physicists had relatively high workloads (NASA TLX range, 51-63). NASA TLX scores for physicians, radiation therapists, and dosimetrists ranged from 40-52. There was marked intertask/professional subgroup variation (P<.0001). Mental demand (P<.001), physical demand (P=.001), and effort (P=.006) significantly differed among professional subgroups. Typically, there were 3-5 stressors per cycle of analyzed tasks with the following distribution: interruptions (41.4%), time factors (17%), technical factors (13.6%), teamwork issues (11.6%), patient factors (9.0%), and environmental factors (7.4%). A positive association between workload and frequency of reported radiotherapy incidents by the WHO was found (r = 0.87, P value=.045). Workload level and sources of stressors vary

  17. Quantitative Assessment of Workload and Stressors in Clinical Radiation Oncology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mazur, Lukasz M., E-mail: lukasz_mazur@ncsu.edu; Industrial Extension Service, North Carolina State University, Raleigh, North Carolina; Biomedical Engineering, North Carolina State University, Raleigh, North Carolina

    2012-08-01

    Purpose: Workload level and sources of stressors have been implicated as sources of error in multiple settings. We assessed workload levels and sources of stressors among radiation oncology professionals. Furthermore, we explored the potential association between workload and the frequency of reported radiotherapy incidents by the World Health Organization (WHO). Methods and Materials: Data collection was aimed at various tasks performed by 21 study participants from different radiation oncology professional subgroups (simulation therapists, radiation therapists, physicists, dosimetrists, and physicians). Workload was assessed using National Aeronautics and Space Administration Task-Load Index (NASA TLX). Sources of stressors were quantified using observational methodsmore » and segregated using a standard taxonomy. Comparisons between professional subgroups and tasks were made using analysis of variance ANOVA, multivariate ANOVA, and Duncan test. An association between workload levels (NASA TLX) and the frequency of radiotherapy incidents (WHO incidents) was explored (Pearson correlation test). Results: A total of 173 workload assessments were obtained. Overall, simulation therapists had relatively low workloads (NASA TLX range, 30-36), and physicists had relatively high workloads (NASA TLX range, 51-63). NASA TLX scores for physicians, radiation therapists, and dosimetrists ranged from 40-52. There was marked intertask/professional subgroup variation (P<.0001). Mental demand (P<.001), physical demand (P=.001), and effort (P=.006) significantly differed among professional subgroups. Typically, there were 3-5 stressors per cycle of analyzed tasks with the following distribution: interruptions (41.4%), time factors (17%), technical factors (13.6%), teamwork issues (11.6%), patient factors (9.0%), and environmental factors (7.4%). A positive association between workload and frequency of reported radiotherapy incidents by the WHO was found (r = 0.87, P value=.045

  18. Training improves laparoscopic tasks performance and decreases operator workload.

    PubMed

    Hu, Jesse S L; Lu, Jirong; Tan, Wee Boon; Lomanto, Davide

    2016-05-01

    It has been postulated that increased operator workload during task performance may increase fatigue and surgical errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a validated tool for self-assessment for workload. Our study aims to assess the relationship of workload and performance of novices in simulated laparoscopic tasks of different complexity levels before and after training. Forty-seven novices without prior laparoscopic experience were recruited in a trial to investigate whether training improves task performance as well as mental workload. The participants were tested on three standard tasks (ring transfer, precision cutting and intracorporeal suturing) in increasing complexity based on the Fundamentals of Laparoscopic Surgery (FLS) curriculum. Following a period of training and rest, participants were tested again. Test scores were computed from time taken and time penalties for precision errors. Test scores and NASA-TLX scores were recorded pre- and post-training and analysed using paired t tests. One-way repeated measures ANOVA was used to analyse differences in NASA-TLX scores between the three tasks. NASA-TLX score was lowest with ring transfer and highest with intracorporeal suturing. This was statistically significant in both pre-training (p < 0.001) and post-training (p < 0.001). NASA-TLX scores mirror the changes in test scores for the three tasks. Workload scores decreased significantly after training for all three tasks (ring transfer = 2.93, p < 0.001, precision cutting = 3.74, p < 0.001, intracorporeal suturing = 2.98, p < 0.001). NASA-TLX score is an accurate reflection of the complexity of simulated laparoscopic tasks in the FLS curriculum. This also correlates with the relationship of test scores between the three tasks. Simulation training improves both performance score and workload score across the tasks.

  19. Subjective evaluation of physical and mental workload interactions across different muscle groups.

    PubMed

    Mehta, Ranjana K; Agnew, Michael J

    2015-01-01

    Both physical and mental demands, and their interactions, have been shown to increase biomechanical loading and physiological reactivity as well as impair task performance. Because these interactions have shown to be muscle-dependent, the aim of this study was to determine the sensitivity of the NASA Task Load Index (NASA TLX) and Ratings of Perceived Exertion (RPE) to evaluate physical and mental workload during muscle-specific tasks. Twenty-four participants performed upper extremity and low back exertions at three physical workload levels in the absence and presence of a mental stressor. Outcome measures included RPE and NASA TLX (six sub-scales) ratings. The findings indicate that while both RPEs and NASA TLX ratings were sensitive to muscle-specific changes in physical demand, only an additional mental stressor and its interaction with either physical demand or muscle groups influenced the effort sub-scale and overall workload scores of the NASA TLX. While additional investigations in actual work settings are warranted, the NASA TLX shows promise in evaluating perceived workload that is sensitive not only to physical and mental demands but also sensitive in determining workload for tasks that employ different muscle groups.

  20. Using Mobile TLA as a Logic for Dynamic I/O Automata

    NASA Astrophysics Data System (ADS)

    Kapus, Tatjana

    Input/Output (I/O) automata and the Temporal Logic of Actions (TLA) are two well-known techniques for the specification and verification of concurrent systems. Over the past few years, they have been extended to the so-called dynamic I/O automata and, respectively, Mobile TLA (MTLA) in order to be more appropriate for mobile agent systems. Dynamic I/O automata is just a mathematical model, whereas MTLA is a logic with a formally defined language. In this paper, therefore, we investigate how MTLA could be used as a formal language for the specification of dynamic I/O automata. We do this by writing an MTLA specification of a travel agent system which has been specified semi-formally in the literature on that model. In this specification, we deal with always existing agents as well as with an initially unknown number of dynamically created agents, with mobile and non-mobile agents, with I/O-automata-style communication, and with the changing communication capabilities of mobile agents. We have previously written a TLA specification of this system. This paper shows that an MTLA specification of such a system can be more elegant and faithful to the dynamic I/O automata definition because the agent existence and location can be expressed directly by using agent and location names instead of special variables as in TLA. It also shows how the reuse of names for dynamically created and destroyed agents within the dynamic I/O automata framework can be specified in MTLA.

  1. Structural Insights into the TLA-3 Extended-Spectrum β-Lactamase and Its Inhibition by Avibactam and OP0595

    PubMed Central

    Jin, Wanchun; Yamaguchi, Yoshihiro; Kimura, Kouji; Kumar, Anupriya; Yamada, Mototsugu; Morinaka, Akihiro; Sakamaki, Yoshiaki; Yonezawa, Minoru; Kurosaki, Hiromasa; Arakawa, Yoshichika

    2017-01-01

    ABSTRACT The development of effective inhibitors that block extended-spectrum β-lactamases (ESBLs) and restore the action of β-lactams represents an effective strategy against ESBL-producing Enterobacteriaceae. We evaluated the inhibitory effects of the diazabicyclooctanes avibactam and OP0595 against TLA-3, an ESBL that we identified previously. Avibactam and OP0595 inhibited TLA-3 with apparent inhibitor constants (Ki app) of 1.71 ± 0.10 and 1.49 ± 0.05 μM, respectively, and could restore susceptibility to cephalosporins in the TLA-3-producing Escherichia coli strain. The value of the second-order acylation rate constant (k2/K, where k2 is the acylation rate constant and K is the equilibrium constant) of avibactam [(3.25 ± 0.03) × 103 M−1 · s−1] was closer to that of class C and D β-lactamases (k2/K, <104 M−1 · s−1) than that of class A β-lactamases (k2/K, >104 M−1 · s−1). In addition, we determined the structure of TLA-3 and that of TLA-3 complexed with avibactam or OP0595 at resolutions of 1.6, 1.6, and 2.0 Å, respectively. TLA-3 contains an inverted Ω loop and an extended loop between the β5 and β6 strands (insertion after Ser237), which appear only in PER-type class A β-lactamases. These structures might favor the accommodation of cephalosporins harboring bulky R1 side chains. TLA-3 presented a high catalytic efficiency (kcat/Km) against cephalosporins, including cephalothin, cefuroxime, and cefotaxime. Avibactam and OP0595 bound covalently to TLA-3 via the Ser70 residue and made contacts with residues Ser130, Thr235, and Ser237, which are conserved in ESBLs. Additionally, the sulfate group of the inhibitors formed polar contacts with amino acid residues in a positively charged pocket of TLA-3. Our findings provide a structural template for designing improved diazabicyclooctane-based inhibitors that are effective against ESBL-producing Enterobacteriaceae. PMID:28739781

  2. TLA-1: a new plasmid-mediated extended-spectrum beta-lactamase from Escherichia coli.

    PubMed

    Silva, J; Aguilar, C; Ayala, G; Estrada, M A; Garza-Ramos, U; Lara-Lemus, R; Ledezma, L

    2000-04-01

    Escherichia coli R170, isolated from the urine of an infected patient, was resistant to expanded-spectrum cephalosporins, aztreonam, ciprofloxacin, and ofloxacin but was susceptible to amikacin, cefotetan, and imipenem. This particular strain contained three different plasmids that encoded two beta-lactamases with pIs of 7.0 and 9.0. Resistance to cefotaxime, ceftazidime, aztreonam, trimethoprim, and sulfamethoxazole was transferred by conjugation from E. coli R170 to E. coli J53-2. The transferred plasmid, RZA92, which encoded a single beta-lactamase, was 150 kb in length. The cefotaxime resistance gene that encodes the TLA-1 beta-lactamase (pI 9.0) was cloned from the transconjugant by transformation to E. coli DH5alpha. Sequencing of the bla(TLA-1) gene revealed an open reading frame of 906 bp, which corresponded to 301 amino acid residues, including motifs common to class A beta-lactamases: (70)SXXK, (130)SDN, and (234)KTG. The amino acid sequence of TLA-1 shared 50% identity with the CME-1 chromosomal class A beta-lactamase from Chryseobacterium (Flavobacterium) meningosepticum; 48.8% identity with the VEB-1 class A beta-lactamase from E. coli; 40 to 42% identity with CblA of Bacteroides uniformis, PER-1 of Pseudomonas aeruginosa, and PER-2 of Salmonella typhimurium; and 39% identity with CepA of Bacteroides fragilis. The partially purified TLA-1 beta-lactamase had a molecular mass of 31.4 kDa and a pI of 9.0 and preferentially hydrolyzed cephaloridine, cefotaxime, cephalothin, benzylpenicillin, and ceftazidime. The enzyme was markedly inhibited by sulbactam, tazobactam, and clavulanic acid. TLA-1 is a new extended-spectrum beta-lactamase of Ambler class A.

  3. Application of Avatars in Display Design to Support Spatial Awareness under Varying Workload Conditions

    DTIC Science & Technology

    2006-09-01

    36 5. NASA - TLX over Increased Workload ................................... 37 viii C...AERONAUTICS AND SPACE ADMINISTRATION – TASK LOAD INDEX ( NASA - TLX )................................................................ 89 APPENDIX H...environments are the NASA Task Load Index ( NASA - TLX ) and the Subjective Workload Assessment Techniques (SWAT) which have subscales assessing loads for time

  4. Structure of a gene encoding a murine thymus leukemia antigen, and organization of Tla genes in the BALB/c mouse

    PubMed Central

    1985-01-01

    We have determined the DNA sequence of a gene encoding a thymus leukemia (TL) antigen in the BALB/c mouse, and have more definitively mapped the cloned BALB/c Tla-region class I gene clusters. Analysis of the sequence shows that the Tla gene is less closely related to the H-2 genes than H-2 genes are to one another or to a Qa-2,3-region genes. The Tla gene, 17.3A, contains an apparent gene conversion. Comparison of the BALB/c Tla genes with those from C57BL shows that BALB/c has more Tla-region class I genes, and that one of the genes absent in C57BL is gene 17.3A. PMID:3894562

  5. TLA-1: a New Plasmid-Mediated Extended-Spectrum β-Lactamase from Escherichia coli

    PubMed Central

    Silva, J.; Aguilar, C.; Ayala, G.; Estrada, M. A.; Garza-Ramos, U.; Lara-Lemus, R.; Ledezma, L.

    2000-01-01

    Escherichia coli R170, isolated from the urine of an infected patient, was resistant to expanded-spectrum cephalosporins, aztreonam, ciprofloxacin, and ofloxacin but was susceptible to amikacin, cefotetan, and imipenem. This particular strain contained three different plasmids that encoded two β-lactamases with pIs of 7.0 and 9.0. Resistance to cefotaxime, ceftazidime, aztreonam, trimethoprim, and sulfamethoxazole was transferred by conjugation from E. coli R170 to E. coli J53-2. The transferred plasmid, RZA92, which encoded a single β-lactamase, was 150 kb in length. The cefotaxime resistance gene that encodes the TLA-1 β-lactamase (pI 9.0) was cloned from the transconjugant by transformation to E. coli DH5α. Sequencing of the blaTLA-1 gene revealed an open reading frame of 906 bp, which corresponded to 301 amino acid residues, including motifs common to class A β-lactamases: 70SXXK, 130SDN, and 234KTG. The amino acid sequence of TLA-1 shared 50% identity with the CME-1 chromosomal class A β-lactamase from Chryseobacterium (Flavobacterium) meningosepticum; 48.8% identity with the VEB-1 class A β-lactamase from E. coli; 40 to 42% identity with CblA of Bacteroides uniformis, PER-1 of Pseudomonas aeruginosa, and PER-2 of Salmonella typhimurium; and 39% identity with CepA of Bacteroides fragilis. The partially purified TLA-1 β-lactamase had a molecular mass of 31.4 kDa and a pI of 9.0 and preferentially hydrolyzed cephaloridine, cefotaxime, cephalothin, benzylpenicillin, and ceftazidime. The enzyme was markedly inhibited by sulbactam, tazobactam, and clavulanic acid. TLA-1 is a new extended-spectrum β-lactamase of Ambler class A. PMID:10722503

  6. Structural Insights into the TLA-3 Extended-Spectrum β-Lactamase and Its Inhibition by Avibactam and OP0595.

    PubMed

    Jin, Wanchun; Wachino, Jun-Ichi; Yamaguchi, Yoshihiro; Kimura, Kouji; Kumar, Anupriya; Yamada, Mototsugu; Morinaka, Akihiro; Sakamaki, Yoshiaki; Yonezawa, Minoru; Kurosaki, Hiromasa; Arakawa, Yoshichika

    2017-10-01

    The development of effective inhibitors that block extended-spectrum β-lactamases (ESBLs) and restore the action of β-lactams represents an effective strategy against ESBL-producing Enterobacteriaceae We evaluated the inhibitory effects of the diazabicyclooctanes avibactam and OP0595 against TLA-3, an ESBL that we identified previously. Avibactam and OP0595 inhibited TLA-3 with apparent inhibitor constants ( K i app ) of 1.71 ± 0.10 and 1.49 ± 0.05 μM, respectively, and could restore susceptibility to cephalosporins in the TLA-3-producing Escherichia coli strain. The value of the second-order acylation rate constant ( k 2 / K , where k 2 is the acylation rate constant and K is the equilibrium constant) of avibactam [(3.25 ± 0.03) × 10 3 M -1 · s -1 ] was closer to that of class C and D β-lactamases ( k 2 / K , <10 4 M -1 · s -1 ) than that of class A β-lactamases ( k 2 / K , >10 4 M -1 · s -1 ). In addition, we determined the structure of TLA-3 and that of TLA-3 complexed with avibactam or OP0595 at resolutions of 1.6, 1.6, and 2.0 Å, respectively. TLA-3 contains an inverted Ω loop and an extended loop between the β5 and β6 strands (insertion after Ser237), which appear only in PER-type class A β-lactamases. These structures might favor the accommodation of cephalosporins harboring bulky R1 side chains. TLA-3 presented a high catalytic efficiency ( k cat / K m ) against cephalosporins, including cephalothin, cefuroxime, and cefotaxime. Avibactam and OP0595 bound covalently to TLA-3 via the Ser70 residue and made contacts with residues Ser130, Thr235, and Ser237, which are conserved in ESBLs. Additionally, the sulfate group of the inhibitors formed polar contacts with amino acid residues in a positively charged pocket of TLA-3. Our findings provide a structural template for designing improved diazabicyclooctane-based inhibitors that are effective against ESBL-producing Enterobacteriaceae . Copyright © 2017 American Society for Microbiology.

  7. Preliminary Investigation of Workload on Intrastate Bus Traffic Controllers

    NASA Astrophysics Data System (ADS)

    Yen Bin, Teo; Azlis-Sani, Jalil; Nur Annuar Mohd Yunos, Muhammad; Ismail, S. M. Sabri S. M.; Tajedi, Noor Aqilah Ahmad

    2016-11-01

    The daily routine of bus traffic controller which involves high mental processes would have a direct impact on the level of workload. To date, the level of workload on the bus traffic controllers in Malaysia is relatively unknown. Excessive workload on bus traffic controllers would affect the control and efficiency of the system. This paper served to study the workload on bus traffic controllers and justify the needs to conduct further detailed research on this field. The objectives of this research are to identify the level of workload on the intrastate bus traffic controllers. Based on the results, recommendations will be proposed for improvements and future studies. The level of workload for the bus traffic controllers is quantified using questionnaire adapted from NASA TLX. Interview sessions were conducted for validation of workload. Sixteen respondents were involved and it was found that the average level of workload based on NASA TLX was 6.91. It was found that workload is not affected by gender and marital status. This study also showed that the level of workload and working experience of bus traffic controllers has a strong positive linear relationship. This study would serve as a guidance and reference related to this field. Since this study is a preliminary investigation, further detailed studies could be conducted to obtain a better comprehension regarding the bus traffic controllers.

  8. A new Tla region antigen Qa-11, similar to Qa-2 and associated with B-type beta 2-microglobulin.

    PubMed

    van de Meugheuvel, W; van Seventer, G; Demant, P

    1985-04-01

    A new antigen, Qa-11, is detected as a 40,000 dalton band in the SDS-PAGE of immunoprecipitates of radiolabeled lymphocyte membrane preparations. In C57BL H-2 congenic strains, its presence is controlled by a gene in the Tla region. In strains with genetic background other than C57BL it is not expressed. Tests with recombinant inbred strains and with H-3 congenic strains show that, in addition to the Tla region, a gene linked to or identical with the beta 2-microglobulin-b-allele is required for the expression of Qa-11 as well. The mobility of the Qa-11 antigen in SDS-PAGE and in isoelectrofocusing is the same as that of Qa-2 antigen. The Cleveland peptide maps of Qa-2 and Qa-11 are identical as well. This finding, that the Tla region controlled Qa-11 antigen is structurally very similar to the Qa-2 antigen, contrasts with the fact that Tla region products do not react with anti-Qa-2 sera. This paradox could be explained by a separate Qa-11 region between Qa-2 and Tla. Alternatively, it is possible that the Qa-11 antigen is the result of the action of a modifying gene in the Tla region upon a Qa-2 gene product, or that the structural gene for Qa-11 is located in the Qa-2 region and a Tla region gene controls its expression.

  9. Structural characteristics of Tla products

    PubMed Central

    1985-01-01

    Biochemical study of thymus leukemia antigen (TL) from thymocytes of various Tla genotypes and from leukemia cells revealed features that, given present evidence, are peculiar to TL among class I products of the H-2:Qa:Tla region of chromosome 17. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE) of TL from thymocytes of all TL+ mouse strains, precipitated by anti-TL antiserum or monoclonal antibodies, showed two closely migrating bands of equal intensity in the heavy (H) chain position (45-50,000 mol wt). Comparison of these two bands by two-dimensional isoelectric focusing (2D IEF)-SDS-PAGE and 2D chymotryptic peptide mapping showed no differences indicative of protein dissimilarity. Thus, the two components of the H chain doublet may differ only in a feature of glycosylation that does not affect charge. The two leukemias studied gave only a single band in the H chain position. On 2D peptide mapping and 2D IEF-SDS-PAGE, the patterns for TL of Tlaa and Tlae thymocytes, which are closely related serologically, were broadly similar, but clearly different from the pattern typical of Tlac and Tlad thymocytes. 2D peptide maps of TL from Tlaa thymocytes and Tlaa leukemia cells did not differ. Leukemia cells of Tlab origin (thymocytes TL-) gave 2D peptide and 2D IEF-SDS-PAGE patterns of a third type. With the exception of Tlaa, thymocytes of TL+ mice yielded additional TL products of higher molecular weight than the TL H chain. PMID:3875681

  10. Personality Traits Moderate the Effect of Workload Sources on Perceived Workload in Flying Column Police Officers

    PubMed Central

    Chiorri, Carlo; Garbarino, Sergio; Bracco, Fabrizio; Magnavita, Nicola

    2015-01-01

    Previous research has suggested that personality traits of the Five Factor Model play a role in worker's response to workload. The aim of this study was to investigate the association of personality traits of first responders with their perceived workload in real-life tasks. A flying column of 269 police officers completed a measure of subjective workload (NASA-Task Load Index) after intervention tasks in a major public event. Officers' scores on a measure of Five Factor Model personality traits were obtained from archival data. Linear Mixed Modeling was used to test the direct and interaction effects of personality traits on workload scores once controlling for background variables, task type and workload source (mental, temporal and physical demand of the task, perceived effort, dissatisfaction for the performance and frustration due to the task). All personality traits except extraversion significantly interacted at least with one workload source. Perceived workload in flying column police officers appears to be the result of their personality characteristics interacting with the workload source. The implications of these results for the development of support measures aimed at reducing the impact of workload in this category of workers are discussed. PMID:26640456

  11. Subjective and objective quantification of physician's workload and performance during radiation therapy planning tasks.

    PubMed

    Mazur, Lukasz M; Mosaly, Prithima R; Hoyle, Lesley M; Jones, Ellen L; Marks, Lawrence B

    2013-01-01

    To quantify, and compare, workload for several common physician-based treatment planning tasks using objective and subjective measures of workload. To assess the relationship between workload and performance to define workload levels where performance could be expected to decline. Nine physicians performed the same 3 tasks on each of 2 cases ("easy" vs "hard"). Workload was assessed objectively throughout the tasks (via monitoring of pupil size and blink rate), and subjectively at the end of each case (via National Aeronautics and Space Administration Task Load Index; NASA-TLX). NASA-TLX assesses the 6 dimensions (mental, physical, and temporal demands, frustration, effort, and performance); scores > or ≈ 50 are associated with reduced performance in other industries. Performance was measured using participants' stated willingness to approve the treatment plan. Differences in subjective and objective workload between cases, tasks, and experience were assessed using analysis of variance (ANOVA). The correlation between subjective and objective workload measures were assessed via the Pearson correlation test. The relationships between workload and performance measures were assessed using the t test. Eighteen case-wise and 54 task-wise assessments were obtained. Subjective NASA-TLX scores (P < .001), but not time-weighted averages of objective scores (P > .1), were significantly lower for the easy vs hard case. Most correlations between the subjective and objective measures were not significant, except between average blink rate and NASA-TLX scores (r = -0.34, P = .02), for task-wise assessments. Performance appeared to decline at NASA-TLX scores of ≥55. The NASA-TLX may provide a reasonable method to quantify subjective workload for broad activities, and objective physiologic eye-based measures may be useful to monitor workload for more granular tasks within activities. The subjective and objective measures, as herein quantified, do not necessarily track each

  12. ISOANTIGENS OF THE H-2 AND Tla LOCI OF THE MOUSE

    PubMed Central

    Boyse, Edward A.; Stockert, Elisabeth; Old, Lloyd J.

    1968-01-01

    H-2 and TL isoantigens of the mouse are specified by the closely linked genetic loci H-2 and Tla. A. study of their representation on thymocytes was performed in order to reveal any interactions between the determinant genes or their products affecting the synthesis or disposition of these components of the thymocyte surface. The method employed was quantitative absorption of cytotoxic antibody by viable thymocytes. The phenotypic expression of TL antigens was found to reduce the demonstrable amount of certain H-2 antigens to as little as 34% of the quantity demonstrable on TL- thymocytes. A reduction was observed in all three H-2 types tested, (H-2b, H-2a, and H-2k). As antigenic modulation (change of TL phenotype from TL+ to TL-, produced by TL antibody) is known to entail a compensatory increase in H-2(D) antigen, it is concluded that the TL phenotype, rather than the Tla genotype, influences the surface representation of H-2 antigens. The two known TL+ phenotypes of thymocytes (TL.2 and TL.1,2,3) depress H-2 equally. The H-2 specificities affected are those determined by the D end of the E-2 locus, which is adjacent to Tla; antigens of the K end, which is distal to Tla, are not depressed. The reduction of demonstrable H-2 antigen on the thymocytes of TL+ x TL- progeny is half that of thymocytes of TL+ x TL+ progeny and the reduction affects equally the products of both H-2 alleles (cis and trans in relation to Tla), indicating that the mechanism of H-2 reduction by TL is extrachromosomal. Whether it involves diminished synthesis of H-2 or steric masking by TL at the cell membrane is unknown, but in either case the reciprocal relation of TL and H-2(D) antigens implies that they probably occupy adjacent positions on thymocytes and that the gene order, H-2(K): H-2(D):Tla is reflected in cell surface structure. Extrachromosomal interaction, apparently involving control of synthesis, occurs also within the TL system of antigens. Thymocytes of TL.2 x TL.1,2,3 progeny

  13. Genomic constitution of an H-2:Tla variant leukemia.

    PubMed Central

    Shen, F W; Chaganti, R S; Doucette, L A; Litman, G W; Steinmetz, M; Hood, L; Boyse, E A

    1984-01-01

    A TL+ leukemia of a (B6 X A)F1 hybrid mouse (H-2b/H-2a) was previously subjected to immunoselection against H-2a by passage in (B6 X A.SW)F1 mice (H-2b/H-2s). A variant leukemia line was obtained that serologically lacked not only the H-2a phenotype but also the TL phenotype determined by the linked cis Tlaa allele of strain A. The H-2b phenotype and the TL phenotype of the Tlab allele of the B6 strain, which is expressed only by leukemia cells, were retained by the variant. Southern blotting with an H-2 cDNA probe that identifies restriction fragment polymorphisms distinguishing alleles of the H-2 and Tla regions of the B6 and A strains indicates that both the H-2a and Tlaa alleles are missing from the genome of this H-2a:Tlaa negative variant. Since the variant has two apparently unaltered chromosomes 17, where the H-2:Tla complex is situated, and since the intensity of bands in Southern blotting is suggestive of H-2b homozygosity, it is considered that loss of the H-2a:Tlaa haplotype by the variant was accompanied by duplication of the H-2b:Tlab haplotype. The implied change from heterozygosity to homozygosity that the variant has undergone with respect to H-2:Tla was not paralleled by a similar change at the three other loci tested, since the variant retained heterozygosity for Pep-3 (chromosome 1), Gpi-1 (chromosome 7), and Es-1 (chromosome 8). Images PMID:6593710

  14. Genomic constitution of an H-2:Tla variant leukemia.

    PubMed

    Shen, F W; Chaganti, R S; Doucette, L A; Litman, G W; Steinmetz, M; Hood, L; Boyse, E A

    1984-10-01

    A TL+ leukemia of a (B6 X A)F1 hybrid mouse (H-2b/H-2a) was previously subjected to immunoselection against H-2a by passage in (B6 X A.SW)F1 mice (H-2b/H-2s). A variant leukemia line was obtained that serologically lacked not only the H-2a phenotype but also the TL phenotype determined by the linked cis Tlaa allele of strain A. The H-2b phenotype and the TL phenotype of the Tlab allele of the B6 strain, which is expressed only by leukemia cells, were retained by the variant. Southern blotting with an H-2 cDNA probe that identifies restriction fragment polymorphisms distinguishing alleles of the H-2 and Tla regions of the B6 and A strains indicates that both the H-2a and Tlaa alleles are missing from the genome of this H-2a:Tlaa negative variant. Since the variant has two apparently unaltered chromosomes 17, where the H-2:Tla complex is situated, and since the intensity of bands in Southern blotting is suggestive of H-2b homozygosity, it is considered that loss of the H-2a:Tlaa haplotype by the variant was accompanied by duplication of the H-2b:Tlab haplotype. The implied change from heterozygosity to homozygosity that the variant has undergone with respect to H-2:Tla was not paralleled by a similar change at the three other loci tested, since the variant retained heterozygosity for Pep-3 (chromosome 1), Gpi-1 (chromosome 7), and Es-1 (chromosome 8).

  15. Psychophysical workload in the operating room: primary surgeon versus assistant.

    PubMed

    Rieger, Annika; Fenger, Sebastian; Neubert, Sebastian; Weippert, Matthias; Kreuzfeld, Steffi; Stoll, Regina

    2015-07-01

    Working in the operating room is characterized by high demands and overall workload of the surgical team. Surgeons often report that they feel more stressed when operating as a primary surgeon than in the function as an assistant which has been confirmed in recent studies. In this study, intra-individual workload was assessed in both intraoperative functions using a multidimensional approach that combined objective and subjective measures in a realistic work setting. Surgeons' intraoperative psychophysiologic workload was assessed through a mobile health system. 25 surgeons agreed to take part in the 24-hour monitoring by giving their written informed consent. The mobile health system contained a sensor electronic module integrated in a chest belt and measuring physiological parameters such as heart rate (HR), breathing rate (BR), and skin temperature. Subjective workload was assessed pre- and postoperatively using an electronic version of the NASA-TLX on a smartphone. The smartphone served as a communication unit and transferred objective and subjective measures to a communication server where data were stored and analyzed. Working as a primary surgeon did not result in higher workload. Neither NASA-TLX ratings nor physiological workload indicators were related to intraoperative function. In contrast, length of surgeries had a significant impact on intraoperative physical demands (p < 0.05; η(2) = 0.283), temporal demands (p < 0.05; η(2) = 0.260), effort (p < 0.05; η(2) = 0.287), and NASA-TLX sum score (p < 0.01; η(2) = 0.287). Intra-individual workload differences do not relate to intraoperative role of surgeons when length of surgery is considered as covariate. An intelligent operating management that considers the length of surgeries by implementing short breaks could contribute to the optimization of intraoperative workload and the preservation of surgeons' health, respectively. The value of mobile health systems for continuous psychophysiologic workload

  16. Assessing workload in neuropsychology: An illustration with the Tower of Hanoi test.

    PubMed

    Hardy, David J; Wright, Matthew J

    2018-05-30

    Workload is a common and useful construct in human factors research that has been largely overlooked in other areas of psychology, including neuropsychology, where it could be effectively employed both theoretically and practically. A popular subjective measure of workload, the NASA-Task Load Index (NASA-TLX), is illustrated with a computerized version of the Tower of Hanoi (TOH), a typical neuropsychological test of executive function. Reported workload, especially as an overall measure and also for the Mental Demand and Effort subscales, was greater in the more difficult TOH conditions and was positively correlated with number of moves to complete the TOH as well as completion time. Thus, results support the utility or construct validity of the NASA-TLX in reflecting workload states in the individual as well as various demands of the neuropsychological test (the timing, physical demands, etc.). It is argued that workload can be a useful construct in neuropsychological assessment, providing an additional channel of information on patient status. For instance, what does it mean if test performance for a patient is at a typical level (indicating no deficit) but workload is exceptionally high?

  17. Economic analysis of temperature-controlled laminar airflow (TLA) for the treatment of patients with severe persistent allergic asthma.

    PubMed

    Brazier, Peter; Schauer, Uwe; Hamelmann, Eckard; Holmes, Steve; Pritchard, Clive; Warner, John O

    2016-01-01

    Chronic asthma is a significant burden for individual sufferers, adversely impacting their quality of working and social life, as well as being a major cost to the National Health Service (NHS). Temperature-controlled laminar airflow (TLA) therapy provides asthma patients at BTS/SIGN step 4/5 an add-on treatment option that is non-invasive and has been shown in clinical studies to improve quality of life for patients with poorly controlled allergic asthma. The objective of this study was to quantify the cost-effectiveness of TLA (Airsonett AB) technology as an add-on to standard asthma management drug therapy in the UK. The main performance measure of interest is the incremental cost per quality-adjusted life year (QALY) for patients using TLA in addition to usual care versus usual care alone. The incremental cost of TLA use is based on an observational clinical study monitoring the incidence of exacerbations with treatment valued using NHS cost data. The clinical effectiveness, used to derive the incremental QALY data, is based on a randomised double-blind placebo-controlled clinical trial comprising participants with an equivalent asthma condition. For a clinical cohort of asthma patients as a whole, the incremental cost-effectiveness ratio (ICER) is £8998 per QALY gained, that is, within the £20 000/QALY cost-effectiveness benchmark used by the National Institute for Health and Care Excellence (NICE). Sensitivity analysis indicates that ICER values range from £18 883/QALY for the least severe patients through to TLA being dominant, that is, cost saving as well as improving quality of life, for individuals with the most severe and poorly controlled asthma. Based on our results, Airsonett TLA is a cost-effective addition to treatment options for stage 4/5 patients. For high-risk individuals with more severe and less well controlled asthma, the use of TLA therapy to reduce incidence of hospitalisation would be a cost saving to the NHS.

  18. Economic analysis of temperature-controlled laminar airflow (TLA) for the treatment of patients with severe persistent allergic asthma

    PubMed Central

    Brazier, Peter; Schauer, Uwe; Hamelmann, Eckard; Holmes, Steve; Pritchard, Clive; Warner, John O

    2016-01-01

    Introduction Chronic asthma is a significant burden for individual sufferers, adversely impacting their quality of working and social life, as well as being a major cost to the National Health Service (NHS). Temperature-controlled laminar airflow (TLA) therapy provides asthma patients at BTS/SIGN step 4/5 an add-on treatment option that is non-invasive and has been shown in clinical studies to improve quality of life for patients with poorly controlled allergic asthma. The objective of this study was to quantify the cost-effectiveness of TLA (Airsonett AB) technology as an add-on to standard asthma management drug therapy in the UK. Methods The main performance measure of interest is the incremental cost per quality-adjusted life year (QALY) for patients using TLA in addition to usual care versus usual care alone. The incremental cost of TLA use is based on an observational clinical study monitoring the incidence of exacerbations with treatment valued using NHS cost data. The clinical effectiveness, used to derive the incremental QALY data, is based on a randomised double-blind placebo-controlled clinical trial comprising participants with an equivalent asthma condition. Results For a clinical cohort of asthma patients as a whole, the incremental cost-effectiveness ratio (ICER) is £8998 per QALY gained, that is, within the £20 000/QALY cost-effectiveness benchmark used by the National Institute for Health and Care Excellence (NICE). Sensitivity analysis indicates that ICER values range from £18 883/QALY for the least severe patients through to TLA being dominant, that is, cost saving as well as improving quality of life, for individuals with the most severe and poorly controlled asthma. Conclusions Based on our results, Airsonett TLA is a cost-effective addition to treatment options for stage 4/5 patients. For high-risk individuals with more severe and less well controlled asthma, the use of TLA therapy to reduce incidence of hospitalisation would be a cost

  19. Relationship between workload and mind-wandering in simulated driving

    PubMed Central

    2017-01-01

    Mental workload and mind-wandering are highly related to driving safety. This study investigated the relationship between mental workload and mind-wandering while driving. Participants (N = 40) were asked to perform a car following task in driving simulator, and report whether they had experienced mind-wandering upon hearing a tone. After driving, participants reported their workload using the NASA-Task Load Index (TLX). Results revealed an interaction between workload and mind-wandering in two different perspectives. First, there was a negative correlation between workload and mind-wandering (r = -0.459, p < 0.01) for different individuals. Second, from temporal perspective workload and mind-wandering frequency increased significantly over task time and were positively correlated. Together, these findings contribute to understanding the roles of workload and mind-wandering in driving. PMID:28467513

  20. Crew workload-management strategies - A critical factor in system performance

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G.

    1989-01-01

    This paper reviews the philosophy and goals of the NASA/USAF Strategic Behavior/Workload Management Program. The philosophical foundation of the program is based on the assumption that an improved understanding of pilot strategies will clarify the complex and inconsistent relationships observed among objective task demands and measures of system performance and pilot workload. The goals are to: (1) develop operationally relevant figures of merit for performance, (2) quantify the effects of strategic behaviors on system performance and pilot workload, (3) identify evaluation criteria for workload measures, and (4) develop methods of improving pilots' abilities to manage workload extremes.

  1. The sensitivity of Galvanic Skin Response for assessing mental workload in Indonesia.

    PubMed

    Widyanti, Ari; Muslim, Khoirul; Sutalaksana, Iftikar Zahedi

    2017-01-01

    Objective measures have been shown to be equally sensitive in different cultures. However, these measures need special devices that are relatively expensive and need expertise to analyze the result. In Indonesia, there is a need for a sensitive and affordable mental workload measure. To evaluate the sensitivity of Galvanic Skin Response (GSR) in assessing mental workload in Indonesia. A total of 72 Indonesian students with normal visual capability. Participants were asked to work on visual memory search task with a secondary task of counting with three different levels of difficulty. GSR, Heart Rate Variability (HRV), and the NASA-TLX were administered prior to, during, and after the tasks. GSR measure was compared to NASA-TLX and HRV measures. Like the HRV, GSR showed to be sensitive in distinguishing rest and task condition significantly but not sensitive in distinguishing different levels of mental workload. In contrast, both the NASA-TLX and performance measure were sensitive in differentiating different levels of mental workload. GSR has potential as a simple, cost-effective tool for measuring mental workload in Indonesia.

  2. Workload, Stress, and Situation Awareness of Soldiers Who are Controlling Unmanned Vehicles in Future Urban Operations

    DTIC Science & Technology

    2007-04-01

    subjective self-ratings of perceived workload, the National Aeronautics and Space Administration ( NASA )-Task Load Index ( TLX ) was used. The NASA TLX ...Staveland, L. E. Development of a NASA - TLX (Task Load Index): Results of Empirical and Theoretical Research. In Human Mental Workload, edited by P.A...system? Please complete the following SHORT surveys (nine questions total) for the missions that you performed today. 19 NASA TLX

  3. Individual differences and subjective workload assessment - Comparing pilots to nonpilots

    NASA Technical Reports Server (NTRS)

    Vidulich, Michael A.; Pandit, Parimal

    1987-01-01

    Results by two groups of subjects, pilots and nonpilots, for two subjective workload assessment techniques (the SWAT and NASA-TLX tests) intended to evaluate individual differences in the perception and reporting of subjective workload are compared with results obtained for several traditional personality tests. The personality tests were found to discriminate between the groups while the workload tests did not. It is concluded that although the workload tests may provide useful information with respect to the interaction between tasks and personality, they are not effective as pure tests of individual differences.

  4. Inflight evaluation of pilot workload measures for rotorcraft research

    NASA Technical Reports Server (NTRS)

    Shively, Robert J.; Bortolussi, Michael R.; Battiste, Vernol; Hart, Sandra G.; Pepitone, David D.; Matsumoto, Joy Hamerman

    1987-01-01

    The effectiveness of heart-rate monitoring and the NASA TLX workload rating scale (Hart et al., 1985) in measuring helicopter-pilot workloads is investigated experimentally. Four NASA test pilots flew two 2-h missions each in an SH-3G helicopter, following scenarios with takeoff, hover, cross-country, and landing tasks; pilot performance on the tasks undertaken near the landing area was measured by laser tracking. The results are presented in graphs and discussed in detail, and it is found that the TLX ratings clearly distinguish the flight segments and are well correlated with the performance data. The mean heart rate (measured as interbeat interval) is correlated (r = -0.69) with the TLX workload, but only the standard deviation of the interbeat interval is able to distinguish between flight segments; the correlation between standard deviation and TLX ratings is negative but not significant.

  5. Workload differences across command levels and emergency response organizations during a major joint training exercise.

    PubMed

    Prytz, Erik G; Rybing, Jonas; Jonson, Carl-Oscar

    2016-01-01

    This study reports on an initial test using a validated workload measurement method, the NASA Task Load Index (TLX), as an indicator of joint emergency exercise effectiveness. Prior research on emergency exercises indicates that exercises must be challenging, ie, result in high workload, to be effective. However, this is often problematic with some participants being underloaded and some overloaded. The NASA TLX was used to test for differences in workload between commanders and subordinates and among three different emergency response organizations during a joint emergency exercise. Questionnaire-based evaluation with professional emergency responders. The study was performed in conjunction with a large-scale interorganizational joint emergency exercise in Sweden. A total of 20 participants from the rescue services, 12 from the emergency medical services, and 12 from the police participated in the study (N=44). Ten participants had a command-level role during the exercise and the remaining 34 were subordinates. The main outcome measures were the workload subscales of the NASA TLX: mental demands, physical demands, temporal demands, performance, effort, and frustration. The results showed that the organizations experienced different levels of workload, that the commanders experienced a higher workload than the subordinates, and that two out of three organizations fell below the twenty-fifth percentile of average workload scores compiled from 237 prior studies. The results support the notion that the NASA TLX could be a useful complementary tool to evaluate exercise designs and outcomes. This should be further explored and verified in additional studies.

  6. The Effects of Workload Transitions in a Multitasking Environment

    DTIC Science & Technology

    2016-09-13

    completed the NASA Task Load Index to assess subjective workload, and the shortened Dundee Stress State Questionnaire to measure subjective task-related...and the analysis of both the NASA Task Load Index and of the shortened Dundee State Questionnaire did not reveal any significant differences related...Electroencepholography (EEG), NASA Task Load Index ( NASA TLX), Dundee Stress State Questionnaire (DSSQ), Hysteresis 16. SECURITY CLASSIFICATION OF

  7. Patients' characteristics and healthcare providers' perceived workload in French hospital emergency wards.

    PubMed

    Schoenenberger, Sandrine; Moulin, Pierre; Brangier, Eric; Gilibert, Daniel

    2014-01-01

    The aim of this research is to understand how patients' characteristics increase healthcare providers' perceived workload. Patients' characteristics and dependency, technical and relational complexities of care seem to increase healthcare providers' workload. As workload is multidimensional, we examine which dimensions are affected by patients' characteristics. Our methodology is based on 121 patients assessed with the NASA task load index (NASA-TLX) and a questionnaire filled in by 57 health providers in 2 emergency wards in French hospital settings, to evaluate their attitudes to different patients' characteristics. Our results show that physical demand is the dimension most affected by patients' behaviour and characteristics. Next, we observe that workload increases more due to patients' behaviour than their social characteristics. We propose that a regulation mechanism be taken into account in further research, using methodology based on observations to identify how healthcare providers might adapt their activities to compensate for workload variations caused by patients.

  8. The effects of practice on tracking and subjective workload

    NASA Technical Reports Server (NTRS)

    Hancock, P. A.; Robinson, M. A.; Chu, A. L.; Hansen, D. R.; Vercruyssen, M.

    1989-01-01

    Six college-age male subjects performed one hundred, two-minute trials on a second-order tracking task. After each trial, subjects estimated perceived workload using both the NASA TLX and SWAT workload assessment procedures. Results confirmed an expected performance improvement on the tracking task which followed traditional learning curves within the performance of each individual. Perceived workload also decreased for both scales across trials. While performance variability significantly decreased across trials, workload variability remained constant. One month later, the same subjects returned to complete the second experiment in the sequence which was a retention replication of the first experiment. Results replicated those for the first experiment except that both performance error and workload were at reduced overall levels. Results in general affirm a parallel workload reduction with performance improvement, an observation consistent with a resource-based view of automaticity.

  9. Comparison of workload measures on computer-generated primary flight displays

    NASA Technical Reports Server (NTRS)

    Nataupsky, Mark; Abbott, Terence S.

    1987-01-01

    Four Air Force pilots were used as subjects to assess a battery of subjective and physiological workload measures in a flight simulation environment in which two computer-generated primary flight display configurations were evaluated. A high- and low-workload task was created by manipulating flight path complexity. Both SWAT and the NASA-TLX were shown to be effective in differentiating the high and low workload path conditions. Physiological measures were inconclusive. A battery of workload measures continues to be necessary for an understanding of the data. Based on workload, opinion, and performance data, it is fruitful to pursue research with a primary flight display and a horizontal situation display integrated into a single display.

  10. Single-Pilot Workload Management

    NASA Technical Reports Server (NTRS)

    Rogers, Jason; Williams, Kevin; Hackworth, Carla; Burian, Barbara; Pruchnicki, Shawn; Christopher, Bonny; Drechsler, Gena; Silverman, Evan; Runnels, Barry; Mead, Andy

    2013-01-01

    Integrated glass cockpit systems place a heavy cognitive load on pilots (Burian Dismukes, 2007). Researchers from the NASA Ames Flight Cognition Lab and the FAA Flight Deck Human Factors Lab examined task and workload management by single pilots. This poster describes pilot performance regarding programming a reroute while at cruise and meeting a waypoint crossing restriction on the initial descent.

  11. Development of the CarMen-Q Questionnaire for mental workload assessment.

    PubMed

    Rubio-Valdehita, Susana; López-Núñez, María I; López-Higes, Ramón; Díaz-Ramiro, Eva M

    2017-11-01

    Mental workload has emerged as one of the most important occupational risk factors present in most psychological and physical diseases caused by work. In view of the lack of specific tools to assess mental workload, the objective of this research was to assess the construct validity and reliability of a new questionnaire for mental workload assessment (CarMen-Q). The sample was composed of 884 workers from several professional sectors, between 18 and 65 years old, 53.4% men and 46.6% women. To evaluate the validity based on relationships with other measures, the NASA-TLX scale was also administered. Confirmatory factor analysis showed an internal structure made up of four dimensions: cognitive, temporal and emotional demands and performance requirement. The results show satisfactory evidence of validity based on relationships with NASA-TLX and good reliability. The questionnaire has good psychometric properties and can be an easy, brief, useful tool for mental workload diagnosis and prevention.

  12. Intraocular pressure is sensitive to cumulative and instantaneous mental workload.

    PubMed

    Vera, Jesús; Jiménez, Raimundo; García, José Antonio; Cárdenas, David

    2017-04-01

    We used a repeated-measures design to assess the impact of mental-task complexity on intraocular pressure (IOP). Fourteen participants performed three continuous 11-min blocks of a mental-workload task (3-back) and an oddball version of this task. Also, heart-rate variability (HRV), cognitive-performance scores, and subjective measure of mental load (NASA-TLX) were determined. IOP was taken before each block and afterwards as well as after recovery from mental tasks. We found that IOP increased during heavy mental workloads (p < 0.01). Consistent with this finding, the autonomic control (HRV) and the cognitive performance were significantly lower (p < 0.045, and p < 0.01, respectively), and the NASA-TLX scores were higher during the 3-back task (p < 0.01). We conclude that IOP is sensitive to mental workload, and it could provide a novel neuroergonomic tool to assess mental workload. Our study highlights a potential association between IOP and the nervous system's state of activation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Physiological Metrics of Mental Workload: A Review of Recent Progress

    DTIC Science & Technology

    1990-06-01

    been found to be more resistant to vigilance decrements than stabiles ( Hastrup , 1979; Sostek, 1978; Vossel & Rossman, 1984), respond more quickly in...NASA workload ratings: A paper and pencil package (NASA Technical Report). Moffett Field, CA: Ames Research Center. Hastrup , J. (1979). Effects of

  14. An Approach to Quantify Workload in a System of Agents

    NASA Technical Reports Server (NTRS)

    Stocker, Richard; Rungta, Neha; Mercer, Eric; Raimondi, Franco; Holbrook, Jon; Cardoza, Colleen; Goodrich, Michael

    2015-01-01

    The role of humans in aviation and other domains continues to shift from manual control to automation monitoring. Studies have found that humans are often poorly suited for monitoring roles, and workload can easily spike in off-nominal situations. Current workload measurement tools, like NASA TLX, use human operators to assess their own workload after using a prototype system. Such measures are used late in the design process and can result in ex- pensive alterations when problems are discovered. Our goal in this work is to provide a quantitative workload measure for use early in the design process. We leverage research in human cognition to de ne metrics that can measure workload on belief-desire-intentions based multi-agent systems. These measures can alert designers to potential workload issues early in design. We demonstrate the utility of our approach by characterizing quantitative differences in the workload for a single pilot operations model compared to a traditional two pilot model.

  15. The Effects of Automation on Battle Manager Workload and Performance

    DTIC Science & Technology

    2008-01-01

    such as the National Aeronautics and Space Administration ( NASA ) Task Load Index ( TLX ) (Hart & Staveland, 1988), the Subjec- tive Workload Assessment...Factor Metric Experience Demographic questionnaire Stress level NASA TLX SWAT Assessment Observer reports Confidence Logged performance data...Mahwah, New Jersey: Law- rence Erlbaum Associates. Hart, S. G., & Staveland, L. E. (1988). Development of NASA - TLX (Task Load Index): Results of

  16. DISTRIBUTION OF URANIUM, ZIRCONIUM, NIOBIUM, RUTHENIUM AND CERIUM BETWEEN NITRIC ACID SOLUTIONS AND 10% TLA-5% OCTYL ALCOHOL/SHELL SOL-T

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lopez-Menchero, E.; Centeno, J.; Magni, G.

    1962-03-01

    The extraction of traces of Ru, Zr, Nb, Ce, and U at low concentrations (5 mg/l in aqueous solution) from nitric acid solutions using trilauryl amine (TLA) has been experimentally studied. TLA will eventually be used for final purification of plutonium. Room-temperature data on plutonium contaminant distribution between aqueous solutions of varying nitric acid concentrations and a Shellsol-T solution containing l0% TlA and 5% octyl alcohol are presented. Within the temperature and nitric acid concentration ranges tested, the extractability of uranium increased with increased acid concentrations, although acid concentration in the aqueous phase had no effect on the decontamination factorsmore » for the main fission products. (H.G.G.)« less

  17. Experimental Evaluation and Workload Characterization for High-Performance Computer Architectures

    NASA Technical Reports Server (NTRS)

    El-Ghazawi, Tarek A.

    1995-01-01

    This research is conducted in the context of the Joint NSF/NASA Initiative on Evaluation (JNNIE). JNNIE is an inter-agency research program that goes beyond typical.bencbking to provide and in-depth evaluations and understanding of the factors that limit the scalability of high-performance computing systems. Many NSF and NASA centers have participated in the effort. Our research effort was an integral part of implementing JNNIE in the NASA ESS grand challenge applications context. Our research work under this program was composed of three distinct, but related activities. They include the evaluation of NASA ESS high- performance computing testbeds using the wavelet decomposition application; evaluation of NASA ESS testbeds using astrophysical simulation applications; and developing an experimental model for workload characterization for understanding workload requirements. In this report, we provide a summary of findings that covers all three parts, a list of the publications that resulted from this effort, and three appendices with the details of each of the studies using a key publication developed under the respective work.

  18. [Study on mental workload of teachers in primary schools].

    PubMed

    Xiao, Yuan-mei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia; Fan, Guang-qin; Feng, Chang

    2011-12-01

    To investigate the distribution characteristics and influencing factors of mental workload of teachers in primary schools. National Aeronautics and Space Administration-Task Load Index (NASA-TLX) was used to assess the mental workload levels for 397 teachers of primary schools in a city. The mental workload (64.34+10.56) of female teachers was significantly higher than that (61.73+ 9.77) of male teachers (P<0.05). The mental workload (65.66+10.42) of "-35" years old group was the highest. When age of teachers was younger than 35 years old, there was a positive correlation between the mental workload and age (r=0.146, P<0.05). When age of teachers was older than 35 years old, there was a negative correlation between the mental workload and age (r=-0.190, P<0.05). The teachers with higher education level felt higher mental workload (unstandardized coefficients B=1.524, standardized coefficients /=0.111, P<0.05). There was a positive correlation between the mental workload and working hours per day (unstandardized coefficients B =4.659, standardized coefficients/3 =0.223, P<0.001). Mental workload of the teachers in primary schools is closely related to age, educational level and work hours per day. Work hours per day is an important risk factor for mental workload. Reducing work hours per day (8 hours) is an effective measure of alleviating the mental workload of teachers in primary schools.

  19. The Workload Curve: Subjective Mental Workload.

    PubMed

    Estes, Steven

    2015-11-01

    In this paper I begin looking for evidence of a subjective workload curve. Results from subjective mental workload assessments are often interpreted linearly. However, I hypothesized that ratings of subjective mental workload increase nonlinearly with unitary increases in working memory load. Two studies were conducted. In the first, the participant provided ratings of the mental difficulty of a series of digit span recall tasks. In the second study, participants provided ratings of mental difficulty associated with recall of visual patterns. The results of the second study were then examined using a mathematical model of working memory. An S curve, predicted a priori, was found in the results of both the digit span and visual pattern studies. A mathematical model showed a tight fit between workload ratings and levels of working memory activation. This effort provides good initial evidence for the existence of a workload curve. The results support further study in applied settings and other facets of workload (e.g., temporal workload). Measures of subjective workload are used across a wide variety of domains and applications. These results bear on their interpretation, particularly as they relate to workload thresholds. © 2015, Human Factors and Ergonomics Society.

  20. Research papers and publications (1981-1987): Workload research program

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G. (Compiler)

    1987-01-01

    An annotated bibliography of the research reports written by participants in NASA's Workload Research Program since 1981 is presented, representing the results of theoretical and applied research conducted at Ames Research Center and at universities and industrial laboratories funded by the program. The major program elements included: 1) developing an understanding of the workload concept; 2) providing valid, reliable, and practical measures of workload; and 3) creating a computer model to predict workload. The goal is to provide workload-related design principles, measures, guidelines, and computational models. The research results are transferred to user groups by establishing close ties with manufacturers, civil and military operators of aerospace systems, and regulatory agencies; publishing scientific articles; participating in and sponsoring workshops and symposia; providing information, guidelines, and computer models; and contributing to the formulation of standards. In addition, the methods and theories developed have been applied to specific operational and design problems at the request of a number of industry and government agencies.

  1. Academic context and perceived mental workload of psychology students.

    PubMed

    Rubio-Valdehita, Susana; López-Higes, Ramón; Díaz-Ramiro, Eva

    2014-01-01

    The excessive workload of university students is an academic stressor. Consequently, it is necessary to evaluate and control the workload in education. This research applies the NASA-TLX scale, as a measure of the workload. The objectives of this study were: (a) to measure the workload levels of a sample of 367 psychology students, (b) to group students according to their positive or negative perception of academic context (AC) and c) to analyze the effects of AC on workload. To assess the perceived AC, we used an ad hoc questionnaire designed according to Demand-Control-Social Support and Effort-Reward Imbalance models. Using cluster analysis, participants were classified into two groups (positive versus negative context). The differences between groups show that a positive AC improves performance (p < .01) and reduces feelings of overload (p < .02), temporal demand (p < .02), and nervousness and frustration (p < .001). Social relationships with peers and teachers, student autonomy and result satisfaction were relevant dimensions of the AC (p < .001 in all cases).

  2. Voice measures of workload in the advanced flight deck: Additional studies

    NASA Technical Reports Server (NTRS)

    Schneider, Sid J.; Alpert, Murray

    1989-01-01

    These studies investigated acoustical analysis of the voice as a measure of workload in individual operators. In the first study, voice samples were recorded from a single operator during high, medium, and low workload conditions. Mean amplitude, frequency, syllable duration, and emphasis all tended to increase as workload increased. In the second study, NASA test pilots performed a laboratory task, and used a flight simulator under differing work conditions. For two of the pilots, high workload in the simulator brought about greater amplitude, peak duration, and stress. In both the laboratory and simulator tasks, high workload tended to be associated with more statistically significant drop-offs in the acoustical measures than were lower workload levels. There was a great deal of intra-subject variability in the acoustical measures. The results suggested that in individual operators, increased workload might be revealed by high initial amplitude and frequency, followed by rapid drop-offs over time.

  3. Single-pilot workload management in entry-level jets.

    DOT National Transportation Integrated Search

    2013-09-01

    Researchers from the NASA Ames Flight Cognition Lab and the FAAs Flight Deck Human Factors Research Laboratory at the Civil Aerospace Medical Institute (CAMI) examined task and workload management by single pilots in Very Light Jets (VLJs), also c...

  4. Evaluation of Mental Workload among ICU Ward's Nurses.

    PubMed

    Mohammadi, Mohsen; Mazloumi, Adel; Kazemi, Zeinab; Zeraati, Hojat

    2015-01-01

    High level of workload has been identified among stressors of nurses in intensive care units (ICUs). The present study investigated nursing workload and identified its influencing perfor-mance obstacles in ICUs. This cross-sectional study was conducted, in 2013, on 81 nurses working in ICUs in Imam Khomeini Hospital in Tehran, Iran. NASA-TLX was applied for assessment of workload. Moreover, ICUs Performance Obstacles Questionnaire was used to identify performance obstacles associated with ICU nursing. Physical demand (mean=84.17) was perceived as the most important dimensions of workload by nurses. The most critical performance obstacles affecting workload included: difficulty in finding a place to sit down, hectic workplace, disorganized workplace, poor-conditioned equipment, waiting for using a piece of equipment, spending much time seeking for supplies in the central stock, poor quality of medical materials, delay in getting medications, unpredicted problems, disorganized central stock, outpatient surgery, spending much time dealing with family needs, late, inadequate, and useless help from nurse assistants, and ineffective morning rounds (P-value<0.05). Various performance obstacles are correlated with nurses' workload, affirms the significance of nursing work system characteristics. Interventions are recommended based on the results of this study in the work settings of nurses in ICUs.

  5. Evaluation of Mental Workload among ICU Ward's Nurses

    PubMed Central

    Mohammadi, Mohsen; Mazloumi, Adel; Kazemi, Zeinab; Zeraati, Hojat

    2015-01-01

    Background: High level of workload has been identified among stressors of nurses in intensive care units (ICUs). The present study investigated nursing workload and identified its influencing perfor­mance obstacles in ICUs. Methods: This cross-sectional study was conducted, in 2013, on 81 nurses working in ICUs in Imam Khomeini Hospital in Tehran, Iran. NASA-TLX was applied for assessment of workload. Moreover, ICUs Performance Obstacles Questionnaire was used to identify performance obstacles associated with ICU nursing. Results: Physical demand (mean=84.17) was perceived as the most important dimensions of workload by nurses. The most critical performance obstacles affecting workload included: difficulty in finding a place to sit down, hectic workplace, disorganized workplace, poor-conditioned equipment, waiting for using a piece of equipment, spending much time seeking for supplies in the central stock, poor quality of medical materials, delay in getting medications, unpredicted problems, disorganized central stock, outpatient surgery, spending much time dealing with family needs, late, inadequate, and useless help from nurse assistants, and ineffective morning rounds (P-value<0.05). Conclusion: Various performance obstacles are correlated with nurses' workload, affirms the significance of nursing work system characteristics. Interventions are recommended based on the results of this study in the work settings of nurses in ICUs. PMID:26933647

  6. Mental workload associated with operating an agricultural sprayer: an empirical approach.

    PubMed

    Dey, A K; Mann, D D

    2011-04-01

    Agricultural spraying involves two major tasks: guiding a sprayer in response to a GPS navigation device, and simultaneous monitoring of rear-attached booms under various illumination and terrain difficulty levels. The aim of the present study was to investigate the effect of illumination, task difficulty, and task level on the mental workload of an individual operating an agricultural sprayer in response to a commercial GPS lightbar, and to explore the sensitivity of the NASA-TLX and SSWAT subjective rating scales in discriminating the subjective experienced workload under various task, illumination, and difficulty levels. Mental workload was measured using performance measures (lateral root mean square error and reaction time), physiological measures (0.1 Hz power of HRV, latency of the P300 component of event-related potential, and eye-glance behavior), and two subjective rating scales (NASA-TLX and SSWAT). Sixteen male university students participated in this experiment, and a fixed-base high-fidelity agricultural tractor simulator was used to create a simulated spraying task. All performance measures, the P300 latency, and subjective rating scales showed a common trend that mental workload increased with the change in illumination from day to night, with task difficulty from low to high, and with task type from single to dual. The 0.1 Hz power of HRV contradicted the performance measures. Eye-glance data showed that under night illumination, participants spent more time looking at the lightbar for guidance information. A similar trend was observed with the change in task type from single to dual. Both subjective rating scales showed a common trend of increasing mental workload with the change in illumination, difficulty, and task levels. However, the SSWAT scale was more sensitive than the NASA-TLX scale. With the change in illumination, difficulty, and task levels, participants spent more mental resources to meet the increased task demand; hence, the

  7. Comparison of NASA-TLX scale, Modified Cooper-Harper scale and mean inter-beat interval as measures of pilot mental workload during simulated flight tasks.

    PubMed

    Mansikka, Heikki; Virtanen, Kai; Harris, Don

    2018-04-30

    The sensitivity of NASA-TLX scale, modified Cooper-Harper (MCH) scale and the mean inter-beat interval (IBI) of successive heart beats, as measures of pilot mental workload (MWL), were evaluated in a flight training device (FTD). Operational F/A-18C pilots flew instrument approaches with varying task loads. Pilots' performance, subjective MWL ratings and IBI were measured. Based on the pilots' performance, three performance categories were formed; high-, medium- and low-performance. Values of the subjective rating scales and IBI were compared between categories. It was found that all measures were able to differentiate most task conditions and there was a strong, positive correlation between NASA-TLX and MCH scale. An explicit link between IBI, NASA-TLX, MCH and performance was demonstrated. While NASA-TLX, MCH and IBI have all been previously used to measure MWL, this study is the first one to investigate their association in a modern FTD, using a realistic flying mission and operational pilots.

  8. Isoantigens of the H-2 and Tla loci of the mouse: interactions affecting their representation on thymocytes.

    PubMed

    Boyse, E A; Stockert, E; Old, L J

    1968-07-01

    H-2 and TL isoantigens of the mouse are specified by the closely linked genetic loci H-2 and Tla. A. study of their representation on thymocytes was performed in order to reveal any interactions between the determinant genes or their products affecting the synthesis or disposition of these components of the thymocyte surface. The method employed was quantitative absorption of cytotoxic antibody by viable thymocytes. The phenotypic expression of TL antigens was found to reduce the demonstrable amount of certain H-2 antigens to as little as 34% of the quantity demonstrable on TL- thymocytes. A reduction was observed in all three H-2 types tested, (H-2(b), H-2(a), and H-2(k)). As antigenic modulation (change of TL phenotype from TL+ to TL-, produced by TL antibody) is known to entail a compensatory increase in H-2(D) antigen, it is concluded that the TL phenotype, rather than the Tla genotype, influences the surface representation of H-2 antigens. The two known TL+ phenotypes of thymocytes (TL.2 and TL.1,2,3) depress H-2 equally. The H-2 specificities affected are those determined by the D end of the E-2 locus, which is adjacent to Tla; antigens of the K end, which is distal to Tla, are not depressed. The reduction of demonstrable H-2 antigen on the thymocytes of TL+ x TL- progeny is half that of thymocytes of TL+ x TL+ progeny and the reduction affects equally the products of both H-2 alleles (cis and trans in relation to Tla), indicating that the mechanism of H-2 reduction by TL is extrachromosomal. Whether it involves diminished synthesis of H-2 or steric masking by TL at the cell membrane is unknown, but in either case the reciprocal relation of TL and H-2(D) antigens implies that they probably occupy adjacent positions on thymocytes and that the gene order, H-2(K): H-2(D):Tla is reflected in cell surface structure. Extrachromosomal interaction, apparently involving control of synthesis, occurs also within the TL system of antigens. Thymocytes of TL.2 x TL.1

  9. Single-pilot workload management in entry-level jets : appendices.

    DOT National Transportation Integrated Search

    2013-09-01

    Researchers from the NASA Ames Flight Cognition Lab and the FAAs Flight Deck Human Factors Research Laboratory at the Civil Aerospace Medical Institute (CAMI) examined task and workload management by single pilots in Very Light Jets (VLJs), also c...

  10. Truncated Photosystem Chlorophyll Antenna Size in the Green Microalga Chlamydomonas reinhardtii upon Deletion of the TLA3-CpSRP43 Gene1[C][W][OA

    PubMed Central

    Kirst, Henning; Garcia-Cerdan, Jose Gines; Zurbriggen, Andreas; Ruehle, Thilo; Melis, Anastasios

    2012-01-01

    The truncated light-harvesting antenna size3 (tla3) DNA insertional transformant of Chlamydomonas reinhardtii is a chlorophyll-deficient mutant with a lighter green phenotype, a lower chlorophyll (Chl) per cell content, and higher Chl a/b ratio than corresponding wild-type strains. Functional analyses revealed a higher intensity for the saturation of photosynthesis and greater light-saturated photosynthetic activity in the tla3 mutant than in the wild type and a Chl antenna size of the photosystems that was only about 40% of that in the wild type. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western-blot analyses showed that the tla3 strain was deficient in the Chl a/b light-harvesting complex. Molecular and genetic analyses revealed a single plasmid insertion in chromosome 4 of the tla3 nuclear genome, causing deletion of predicted gene g5047 and plasmid insertion within the fourth intron of downstream-predicted gene g5046. Complementation studies defined that gene g5047 alone was necessary and sufficient to rescue the tla3 mutation. Gene g5047 encodes a C. reinhardtii homolog of the chloroplast-localized SRP43 signal recognition particle, whose occurrence and function in green microalgae has not hitherto been investigated. Biochemical analysis showed that the nucleus-encoded and chloroplast-localized CrCpSRP43 protein specifically operates in the assembly of the peripheral components of the Chl a/b light-harvesting antenna. This work demonstrates that cpsrp43 deletion in green microalgae can be employed to generate tla mutants with a substantially diminished Chl antenna size. The latter exhibit improved solar energy conversion efficiency and photosynthetic productivity under mass culture and bright sunlight conditions. PMID:23043081

  11. Cognitive workload modulation through degraded visual stimuli: a single-trial EEG study

    NASA Astrophysics Data System (ADS)

    Yu, K.; Prasad, I.; Mir, H.; Thakor, N.; Al-Nashash, H.

    2015-08-01

    Objective. Our experiments explored the effect of visual stimuli degradation on cognitive workload. Approach. We investigated the subjective assessment, event-related potentials (ERPs) as well as electroencephalogram (EEG) as measures of cognitive workload. Main results. These experiments confirm that degradation of visual stimuli increases cognitive workload as assessed by subjective NASA task load index and confirmed by the observed P300 amplitude attenuation. Furthermore, the single-trial multi-level classification using features extracted from ERPs and EEG is found to be promising. Specifically, the adopted single-trial oscillatory EEG/ERP detection method achieved an average accuracy of 85% for discriminating 4 workload levels. Additionally, we found from the spatial patterns obtained from EEG signals that the frontal parts carry information that can be used for differentiating workload levels. Significance. Our results show that visual stimuli can modulate cognitive workload, and the modulation can be measured by the single trial EEG/ERP detection method.

  12. NASA Space Human Factors Program

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This booklet briefly and succinctly treats 23 topics of particular interest to the NASA Space Human Factors Program. Most articles are by different authors who are mainly NASA Johnson or NASA Ames personnel. Representative topics covered include mental workload and performance in space, light effects on Circadian rhythms, human sleep, human reasoning, microgravity effects and automation and crew performance.

  13. Wear measurement of the cutting edge of superhard turning tools using TLA technique

    NASA Astrophysics Data System (ADS)

    Vasváry, L.; Ditrói, F.; Takács, S.; Szabó, Z.; Szűcs, J.; Kundrák, J.; Mahunka, I.

    1994-03-01

    Wear measurement on superhard boron nitride and artificial diamond turning tools was performed using thin layer activation (TLA) technique. The samples were irradiated in two different geometries to improve the sensitivity of the method and change the region of wear to be investigated. The most proper irradiation parameters and nuclear reactions were investigated for both kind of tools.

  14. Evaluating mental workload of two-dimensional and three-dimensional visualization for anatomical structure localization.

    PubMed

    Foo, Jung-Leng; Martinez-Escobar, Marisol; Juhnke, Bethany; Cassidy, Keely; Hisley, Kenneth; Lobe, Thom; Winer, Eliot

    2013-01-01

    Visualization of medical data in three-dimensional (3D) or two-dimensional (2D) views is a complex area of research. In many fields 3D views are used to understand the shape of an object, and 2D views are used to understand spatial relationships. It is unclear how 2D/3D views play a role in the medical field. Using 3D views can potentially decrease the learning curve experienced with traditional 2D views by providing a whole representation of the patient's anatomy. However, there are challenges with 3D views compared with 2D. This current study expands on a previous study to evaluate the mental workload associated with both 2D and 3D views. Twenty-five first-year medical students were asked to localize three anatomical structures--gallbladder, celiac trunk, and superior mesenteric artery--in either 2D or 3D environments. Accuracy and time were taken as the objective measures for mental workload. The NASA Task Load Index (NASA-TLX) was used as a subjective measure for mental workload. Results showed that participants viewing in 3D had higher localization accuracy and a lower subjective measure of mental workload, specifically, the mental demand component of the NASA-TLX. Results from this study may prove useful for designing curricula in anatomy education and improving training procedures for surgeons.

  15. Subjective Mental Workload and Its Correlation With Musculoskeletal Disorders in Bank Staff.

    PubMed

    Darvishi, Ebrahim; Maleki, Afshin; Giahi, Omid; Akbarzadeh, Arash

    2016-01-01

    The purpose of this study was to evaluate the rate of subjective mental workload (SMWL) and its correlation with musculoskeletal disorders among bank staff members in Kurdistan Province located in western Iran. This cross-sectional study was conducted among 200 bank staff members in Kurdistan Province, Iran. The mental workload was assessed using the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) computerized version. NASA-TLX is a multidimensional rating procedure that derives an overall workload score based on a weighted average of ratings on 6 subscales. These subscales include Mental Demands, Physical Demands, Temporal Demands, Performance, Effort, Effectiveness, and Frustration. The musculoskeletal disorders (MSDs) were documented with the Nordic Musculoskeletal Questionnaire and generic body diagram. Of the staff members, 78.5% experienced pain at least once during the past year in 1 of their 9 musculoskeletal body regions. The highest frequencies of pain were in the neck and lower back. The NASA-TLX estimated the Effort and Performance scales with mean ± SD of 72.8 ± 25.2 and 36 ± 22.6, respectively, as the maximal and minimal scores among the 6 subscales of SMWL. The statistical analysis of the data revealed that there was a significant correlation between the overall mental workload score and also among the 6 subscales of SMWL separately with MSDs (P < .05). SMWL appears to be a risk factor in the incidence of MSDs, so that the odds of MSDs increased by 11% with each additional 1-point increase in SMWL score. Copyright © 2016. Published by Elsevier Inc.

  16. Novel method of measuring the mental workload of anaesthetists during clinical practice.

    PubMed

    Byrne, A J; Oliver, M; Bodger, O; Barnett, W A; Williams, D; Jones, H; Murphy, A

    2010-12-01

    Cognitive overload has been recognized as a significant cause of error in industries such as aviation and measuring mental workload has become a key method of improving safety. The aim of this study was to pilot the use of a new method of measuring mental workload in the operating theatre using a previously published methodology. The mental workload of the anaesthetists was assessed by measuring their response times to a wireless vibrotactile device and the NASA TLX subjective workload score during routine surgical procedures. Primary task workload was inferred from the phase of anaesthesia. Significantly increased response time was associated with the induction phase of anaesthesia compared with maintenance/emergence, non-consultant grade, and during more complex cases. Increased response was also associated with self-reported mental load, physical load, and frustration. These findings are consistent with periods of increased mental workload and with the findings of other studies using similar techniques. These findings confirm the importance of mental workload to the performance of anaesthetists and suggest that increased mental workload is likely to be a common problem in clinical practice. Although further studies are required, the method described may be useful for the measurement of the mental workload of anaesthetists.

  17. Cognitive and affective components of mental workload: Understanding the effects of each on human decision making behavior

    NASA Technical Reports Server (NTRS)

    Nygren, Thomas E.

    1992-01-01

    Human factors and ergonomics researchers have recognized for some time the increasing importance of understanding the role of the construct of mental workload in flight research. Current models of mental workload suggest that it is a multidimensional and complex construct, but one that has proved difficult to measure. Because of this difficulty, emphasis has usually been placed on using direct reports through subjective measures such as rating scales to assess levels of mental workload. The NASA Task Load Index (NASA/TLX, Hart and Staveland) has been shown to be a highly reliable and sensitive measure of perceived mental workload. But a problem with measures like TLX is that there is still considerable disagreement as to what it is about mental workload that these subjective measures are actually measuring. The empirical use of subjective workload measures has largely been to provide estimates of the cognitive components of the actual mental workload required for a task. However, my research suggests that these measures may, in fact have greater potential in accurately assessing the affective components of workload. That is, for example, TLX may be more likely to assess the positive and negative feelings associated with varying workload levels, which in turn may potentially influence the decision making behavior that directly bears on performance and safety issues. Pilots, for example, are often called upon to complete many complex tasks that are high in mental workload, stress, and frustration, and that have significant dynamic decision making components -- often ones that involve risk as well.

  18. File-System Workload on a Scientific Multiprocessor

    NASA Technical Reports Server (NTRS)

    Kotz, David; Nieuwejaar, Nils

    1995-01-01

    Many scientific applications have intense computational and I/O requirements. Although multiprocessors have permitted astounding increases in computational performance, the formidable I/O needs of these applications cannot be met by current multiprocessors a their I/O subsystems. To prevent I/O subsystems from forever bottlenecking multiprocessors and limiting the range of feasible applications, new I/O subsystems must be designed. The successful design of computer systems (both hardware and software) depends on a thorough understanding of their intended use. A system designer optimizes the policies and mechanisms for the cases expected to most common in the user's workload. In the case of multiprocessor file systems, however, designers have been forced to build file systems based only on speculation about how they would be used, extrapolating from file-system characterizations of general-purpose workloads on uniprocessor and distributed systems or scientific workloads on vector supercomputers (see sidebar on related work). To help these system designers, in June 1993 we began the Charisma Project, so named because the project sought to characterize 1/0 in scientific multiprocessor applications from a variety of production parallel computing platforms and sites. The Charisma project is unique in recording individual read and write requests-in live, multiprogramming, parallel workloads (rather than from selected or nonparallel applications). In this article, we present the first results from the project: a characterization of the file-system workload an iPSC/860 multiprocessor running production, parallel scientific applications at NASA's Ames Research Center.

  19. Physiological Parameter Response to Variation of Mental Workload.

    PubMed

    Marinescu, Adrian Cornelius; Sharples, Sarah; Ritchie, Alastair Campbell; Sánchez López, Tomas; McDowell, Michael; Morvan, Hervé P

    2018-02-01

    To examine the relationship between experienced mental workload and physiological response by noninvasive monitoring of physiological parameters. Previous studies have examined how individual physiological measures respond to changes in mental demand and subjective reports of workload. This study explores the response of multiple physiological parameters and quantifies their added value when estimating the level of demand. The study presented was conducted in laboratory conditions and required participants to perform a visual-motor task that imposed varying levels of demand. The data collected consisted of physiological measurements (heart interbeat intervals, breathing rate, pupil diameter, facial thermography), subjective ratings of workload (Instantaneous Self-Assessment Workload Scale [ISA] and NASA-Task Load Index), and the performance. Facial thermography and pupil diameter were demonstrated to be good candidates for noninvasive workload measurements: For seven out of 10 participants, pupil diameter showed a strong correlation ( R values between .61 and .79 at a significance value of .01) with mean ISA normalized values. Facial thermography measures added on average 47.7% to the amount of variability in task performance explained by a regression model. As with the ISA ratings, the relationship between the physiological measures and performance showed strong interparticipant differences, with some individuals demonstrating a much stronger relationship between workload and performance measures than others. The results presented in this paper demonstrate that physiological and pupil diameter can be used for noninvasive real-time measurement of workload. The methods presented in this article, with current technological capabilities, are better suited for workplaces where the person is seated, offering the possibility of being applied to pilots and air traffic controllers.

  20. Physiological Parameter Response to Variation of Mental Workload

    PubMed Central

    Marinescu, Adrian Cornelius; Sharples, Sarah; Ritchie, Alastair Campbell; Sánchez López, Tomas; McDowell, Michael; Morvan, Hervé P.

    2017-01-01

    Objective: To examine the relationship between experienced mental workload and physiological response by noninvasive monitoring of physiological parameters. Background: Previous studies have examined how individual physiological measures respond to changes in mental demand and subjective reports of workload. This study explores the response of multiple physiological parameters and quantifies their added value when estimating the level of demand. Method: The study presented was conducted in laboratory conditions and required participants to perform a visual-motor task that imposed varying levels of demand. The data collected consisted of physiological measurements (heart interbeat intervals, breathing rate, pupil diameter, facial thermography), subjective ratings of workload (Instantaneous Self-Assessment Workload Scale [ISA] and NASA-Task Load Index), and the performance. Results: Facial thermography and pupil diameter were demonstrated to be good candidates for noninvasive workload measurements: For seven out of 10 participants, pupil diameter showed a strong correlation (R values between .61 and .79 at a significance value of .01) with mean ISA normalized values. Facial thermography measures added on average 47.7% to the amount of variability in task performance explained by a regression model. As with the ISA ratings, the relationship between the physiological measures and performance showed strong interparticipant differences, with some individuals demonstrating a much stronger relationship between workload and performance measures than others. Conclusion: The results presented in this paper demonstrate that physiological and pupil diameter can be used for noninvasive real-time measurement of workload. Application: The methods presented in this article, with current technological capabilities, are better suited for workplaces where the person is seated, offering the possibility of being applied to pilots and air traffic controllers. PMID:28965433

  1. Hands-free administration of subjective workload scales: acceptability in a surgical training environment.

    PubMed

    Carswell, C Melody; Lio, Cindy H; Grant, Russell; Klein, Martina I; Clarke, Duncan; Seales, W Brent; Strup, Stephen

    2010-12-01

    Subjective workload measures are usually administered in a visual-manual format, either electronically or by paper and pencil. However, vocal responses to spoken queries may sometimes be preferable, for example when experimental manipulations require continuous manual responding or when participants have certain sensory/motor impairments. In the present study, we evaluated the acceptability of the hands-free administration of two subjective workload questionnaires - the NASA Task Load Index (NASA-TLX) and the Multiple Resources Questionnaire (MRQ) - in a surgical training environment where manual responding is often constrained. Sixty-four undergraduates performed fifteen 90-s trials of laparoscopic training tasks (five replications of 3 tasks - cannulation, ring transfer, and rope manipulation). Half of the participants provided workload ratings using a traditional paper-and-pencil version of the NASA-TLX and MRQ; the remainder used a vocal (hands-free) version of the questionnaires. A follow-up experiment extended the evaluation of the hands-free version to actual medical students in a Minimally Invasive Surgery (MIS) training facility. The NASA-TLX was scored in 2 ways - (1) the traditional procedure using participant-specific weights to combine its 6 subscales, and (2) a simplified procedure - the NASA Raw Task Load Index (NASA-RTLX) - using the unweighted mean of the subscale scores. Comparison of the scores obtained from the hands-free and written administration conditions yielded coefficients of equivalence of r=0.85 (NASA-TLX) and r=0.81 (NASA-RTLX). Equivalence estimates for the individual subscales ranged from r=0.78 ("mental demand") to r=0.31 ("effort"). Both administration formats and scoring methods were equally sensitive to task and repetition effects. For the MRQ, the coefficient of equivalence for the hands-free and written versions was r=0.96 when tested on undergraduates. However, the sensitivity of the hands-free MRQ to task demands (

  2. Situation Awareness and Workload Measures for SAFOR

    NASA Technical Reports Server (NTRS)

    DeMaio, Joe; Hart, Sandra G.; Allen, Ed (Technical Monitor)

    1999-01-01

    The present research was conducted in support of the NASA Safe All-Weather Flight Operations for Rotorcraft (SAFOR) program. The purpose of the work was to investigate the utility of two measurement tools developed by the British Defense Evaluation Research Agency. These tools were a subjective workload assessment scale, the DRA Workload Scale (DRAWS), and a situation awareness measurement tool in which the crews self-evaluation of performance is compared against actual performance. These two measurement tools were evaluated in the context of a test of an innovative approach to alerting the crew by way of a helmet mounted display. The DRAWS was found to be usable, but it offered no advantages over extant scales, and it had only limited resolution. The performance self-evaluation metric of situation awareness was found to be highly effective.

  3. [Effects of mental workload on work ability in primary and secondary school teachers].

    PubMed

    Xiao, Yuanmei; Li, Weijuan; Ren, Qingfeng; Ren, Xiaohui; Wang, Zhiming; Wang, Mianzhen; Lan, Yajia

    2015-02-01

    To investigate the change pattern of primary and secondary school teachers' work ability with the changes in their mental workload. A total of 901 primary and secondary school teachers were selected by random cluster sampling, and then their mental workload and work ability were assessed by National Aeronautics and Space Administration-Task Load Index (NASA-TLX) and Work Ability Index (WAI) questionnaires, whose reliability and validity had been tested. The effects of their mental workload on the work ability were analyzed. Primary and secondary school teachers' work ability reached the highest level at a certain level of mental workload (55.73< mental workload ≤ 64.10). When their mental workload was lower than the level, their work ability had a positive correlation with the mental workload. Their work ability increased or maintained stable with the increasing mental workload. Moreover, the percentage of teachers with good work ability increased, while that of teachers with moderate work ability decreased. But when their mental workload was higher than the level, their work ability had a negative correlation with the mental workload. Their work ability significantly decreased with the increasing mental workload (P < 0.01). Furthermore, the percentage of teachers with good work ability decreased, while that of teachers with moderate work ability increased (P < 0.001). Too high or low mental workload will result in the decline of primary and secondary school teachers' work ability. Moderate mental workload (55.73∼64.10) will benefit the maintaining and stabilization of their work ability.

  4. Workflow interruptions and mental workload in hospital pediatricians: an observational study.

    PubMed

    Weigl, Matthias; Müller, Andreas; Angerer, Peter; Hoffmann, Florian

    2014-09-24

    Pediatricians' workload is increasingly thought to affect pediatricians' quality of work life and patient safety. Workflow interruptions are a frequent stressor in clinical work, impeding clinicians' attention and contributing to clinical malpractice. We aimed to investigate prospective associations of workflow interruptions with multiple dimensions of mental workload in pediatricians during clinical day shifts. In an Academic Children's Hospital a prospective study of 28 full shift observations was conducted among pediatricians providing ward coverage. The prevalence of workflow interruptions was based on expert observation using a validated observation instrument. Concurrently, Pediatricians' workload ratings were assessed with three workload dimensions of the well-validated NASA-Task Load Index: mental demands, effort, and frustration. Observed pediatricians were, on average, disrupted 4.7 times per hour. Most frequent were interruptions by colleagues (30.2%), nursing staff (29.7%), and by telephone/beeper calls (16.3%). Interruption measures were correlated with two workload outcomes of interest: frequent workflow interruptions were related to less cognitive demands, but frequent interruptions were associated with increased frustration. With regard to single sources, interruptions by colleagues showed the strongest associations to workload. The findings provide insights into specific pathways between different types of interruptions and pediatricians' mental workload. These findings suggest further research and yield a number of work and organization re-design suggestions for pediatric care.

  5. Suppression of Tla1 gene expression for improved solar conversion efficiency and photosynthetic productivity in plants and algae

    DOEpatents

    Melis, Anastasios; Mitra, Mautusi

    2010-06-29

    The invention provides method and compositions to minimize the chlorophyll antenna size of photosynthesis by decreasing TLA1 gene expression, thereby improving solar conversion efficiencies and photosynthetic productivity in plants, e.g., green microalgae, under bright sunlight conditions.

  6. The effects of control order, feedback, practice, and input device on tracking performance and perceived workload

    NASA Technical Reports Server (NTRS)

    Hancock, P. A.; Robinson, M. A.

    1989-01-01

    The present experiment examined the influence of several task-related factors on tracking performance and concomitant workload. The manipulated factors included tracking order, the presence or absence of knowledge of performance, and the control device. Summed root mean square error (rmse) and perceived workload were measured at the termination of each trial. Perceived workload was measured using the NASA Task Load Index (TLX) and the Subjective Workload Assessment Technique (SWAT). Results indicated a large and expected effect for track order on both performance and the perception of load. In general, trackball input was more accurate and judged for lower load than input using a mouse. The presence or absence of knowledge of performance had little effect on either performance or workload. There were a number of interactions between factors shown in performance that were mirrored by perceived workload scores. Results from each workload scale were equivalent in terms of sensitivity to task manipulations. The pattern of results affirm the utility of these workload measures in assessing the imposed load of multiple task-related variables.

  7. Contribution of mental workload to job stress in industrial workers.

    PubMed

    González-Muñoz, Elvia Luz; Gutiérrez-Martínez, Rodolfo E

    2007-01-01

    This study's central objective is to determine how several individual, organizational and ergonomic factors influence the relationship between job stress and mental workload for workers in an electronics company. A cross-sectional study was made as a test of hypotheses regarding that relationship. The sample is composed of 95 workers, of both sexes, from the electronics industry in the metropolitan zone of Guadalajara, Jalisco, Mexico. Ergonomic conditions were evaluated with the Ergonomic Evaluation List, stress was evaluated by administering the SWS-Survey to groups of subjects, and mental workload was evaluated with the NASA-TLX Workload Index. Using Cochran's and Mantel-Haenzsel statistics, the odds ratio for each of the independent variables was {e}stimated as a risk factor for job stress, and analysis was later conducted by means of logistic regression for those risks found to be significant. Of the 95 worker participants, 26.3% presented a high level of job stress and 17.9% of the workers were found to present high levels of mental workload. The results show that working hours, mental demand, temporal demand, and frustration when faced with a given task may be considered risk factors for job stress.

  8. Quantifying the impact of cross coverage on physician's workload and performance in radiation oncology.

    PubMed

    Mosaly, Prithima R; Mazur, Lukasz M; Jones, Ellen L; Hoyle, Lesley; Zagar, Timothy; Chera, Bhishamjit S; Marks, Lawrence B

    2013-01-01

    To quantitatively assess the difference in workload and performance of radiation oncology physicians during radiation therapy treatment planning tasks under the conditions of "cross coverage" versus planning a patient with whom they were familiar. Eight physicians (3 experienced faculty physicians and 5 physician residents) performed 2 cases. The first case represented a "cross-coverage" scenario where the physicians had no prior information about the case to be planned. The second exposure represented a "regular-coverage" scenario where the physicians were familiar with the patient case to be planned. Each case involved 3 tasks to be completed systematically. Workload was assessed both subjectively (perceived) using National Aeronautics and Space Administration-Task Load Index (NASA-TLX), and objectively (physiological) throughout the task using eye data (via monitoring pupil size and blink rate). Performance of each task and the case was measured using completion time. Subjective willingness to approve or disapprove the generated plan was obtained after completion of the case only. Forty-eight perceived and 48 physiological workload assessments were obtained. Overall, results revealed a significant increase in perceived workload (high NASA-TLX score) and decrease in performance (longer completion time and reduced approval rate) during cross coverage. There were nonsignificant increases in pupil diameter and decreases in the blink rate during cross-coverage versus regular-coverage scenario. In both cross-coverage and regular-coverage scenarios the level of experience did not affect workload and performance. The cross-coverage scenario significantly increases perceived workload and degrades performance versus regular coverage. Hence, to improve patient safety, efforts must be made to develop policies, standard operating procedures, and usability improvements to electronic medical record and treatment planning systems for "easier" information processing to deal with

  9. Fatigue and workload in short and long-haul train driving.

    PubMed

    Kazemi, Zeinab; Mazloumi, Adel; Nasl Saraji, Gabraeil; Barideh, Sedighe

    2016-06-08

    Little has been investigated regarding the role of shift schedule on fatigue and workload among Iranian train drivers. This study sought to compare train drivers' fatigue and workload between a long-haul and a short-haul train trips. One-hundred train drivers, in two routes of Tehran-Mashhad (long-haul) and Tehran-Semnan (short-haul), were asked to complete the Samn-Perelli Fatigue Scale prior to departure, immediately after ending driving duty on the way going, and immediately after ending driving on the way back. Moreover, they were asked to complete NASA-TLX at the end of their shift. Accordingly, understudy train drivers stated relatively similar levels of fatigue and workload for the two trips. Furthermore, fatigue scores were significantly higher at the end of shifts in both routes. Overall, train drivers in long-haul trips had longer rest hours between the ways going and coming back, which seems to compensate for the side effects of longer driving durations.

  10. Nursing workload in the acute-care setting: A concept analysis of nursing workload.

    PubMed

    Swiger, Pauline A; Vance, David E; Patrician, Patricia A

    2016-01-01

    A pressing need in the field of nursing is the identification of optimal staffing levels to ensure patient safety. Effective staffing requires comprehensive measurement of nursing workload to determine staffing needs. Issues surrounding nursing workload are complex, and the volume of workload is growing; however, many workload systems do not consider the numerous workload factors that impact nursing today. The purpose of this concept analysis was to better understand and define nursing workload as it relates to the acute-care setting. Rogers' evolutionary method was used for this literature-based concept analysis. Nursing workload is influenced by more than patient care. The proposed definition of nursing workload may help leaders identify workload that is unnoticed and unmeasured. These findings could help leaders consider and identify workload that is unnecessary, redundant, or more appropriate for assignment to other members of the health care team. Published by Elsevier Inc.

  11. Effects of mental workload on physiological and subjective responses during traffic density monitoring: A field study.

    PubMed

    Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji

    2016-01-01

    This study evaluated operators' mental workload while monitoring traffic density in a city traffic control center. To determine the mental workload, physiological signals (ECG, EMG) were recorded and the NASA-Task Load Index (TLX) was administered for 16 operators. The results showed that the operators experienced a larger mental workload during high traffic density than during low traffic density. The traffic control center stressors caused changes in heart rate variability features and EMG amplitude, although the average workload score was significantly higher in HTD conditions than in LTD conditions. The findings indicated that increasing traffic congestion had a significant effect on HR, RMSSD, SDNN, LF/HF ratio, and EMG amplitude. The results suggested that when operators' workload increases, their mental fatigue and stress level increase and their mental health deteriorate. Therefore, it maybe necessary to implement an ergonomic program to manage mental health. Furthermore, by evaluating mental workload, the traffic control center director can organize the center's traffic congestion operators to sustain the appropriate mental workload and improve traffic control management. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Measurement and analysis of workload effects on fault latency in real-time systems

    NASA Technical Reports Server (NTRS)

    Woodbury, Michael H.; Shin, Kang G.

    1990-01-01

    The authors demonstrate the need to address fault latency in highly reliable real-time control computer systems. It is noted that the effectiveness of all known recovery mechanisms is greatly reduced in the presence of multiple latent faults. The presence of multiple latent faults increases the possibility of multiple errors, which could result in coverage failure. The authors present experimental evidence indicating that the duration of fault latency is dependent on workload. A synthetic workload generator is used to vary the workload, and a hardware fault injector is applied to inject transient faults of varying durations. This method makes it possible to derive the distribution of fault latency duration. Experimental results obtained from the fault-tolerant multiprocessor at the NASA Airlab are presented and discussed.

  13. Improving pilot mental workload evaluation with combined measures.

    PubMed

    Wanyan, Xiaoru; Zhuang, Damin; Zhang, Huan

    2014-01-01

    Behavioral performance, subjective assessment based on NASA Task Load Index (NASA-TLX), as well as physiological measures indexed by electrocardiograph (ECG), event-related potential (ERP), and eye tracking data were used to assess the mental workload (MW) related to flight tasks. Flight simulation tasks were carried out by 12 healthy participants under different MW conditions. The MW conditions were manipulated by setting the quantity of flight indicators presented on the head-up display (HUD) in the cruise phase. In this experiment, the behavioral performance and NASA-TLX could reflect the changes of MW ideally. For physiological measures, the indices of heart rate variability (HRV), P3a, pupil diameter and eyelid opening were verified to be sensitive to MW changes. Our findings can be applied to the comprehensive evaluation of MW during flight tasks and the further quantitative classification.

  14. Estimation of duration and mental workload at differing times of day by males and females

    NASA Technical Reports Server (NTRS)

    Hancock, P. A.; Rodenburg, G. J.; Mathews, W. D.; Vercruyssen, M.

    1988-01-01

    Two experiments are reported which investigated whether male and female operator duration estimation and subjective workload followed conventional circadian fluctuation. In the first experiment, twenty-four subjects performed a filled time-estimation task in a constant blacked-out, noise-reduced environment at 0800, 1200, 1600, and 2000 h. In the second experiment, twelve subjects performed an unfilled time estimation task in similar conditions at 0900, 1400, and 1900 h. At the termination of all experimental sessions, participants completed the NASA TLX workload assessment questionnaire as a measure of perceived mental workload. Results indicated that while physiological response followed an expected pattern, estimations of duration and subjective perception of workload showed no significant effects for time-of-day. In each of the experiments, however, there were significant differences in durational estimates and mental workload response depending upon the gender of the participant. Results are taken to support the assertion that subjective workload is responsive largely to task-related factors and indicates the important differences that may be expected due to operator gender.

  15. Physician activity during outpatient visits and subjective workload.

    PubMed

    Calvitti, Alan; Hochheiser, Harry; Ashfaq, Shazia; Bell, Kristin; Chen, Yunan; El Kareh, Robert; Gabuzda, Mark T; Liu, Lin; Mortensen, Sara; Pandey, Braj; Rick, Steven; Street, Richard L; Weibel, Nadir; Weir, Charlene; Agha, Zia

    2017-05-01

    We describe methods for capturing and analyzing EHR use and clinical workflow of physicians during outpatient encounters and relating activity to physicians' self-reported workload. We collected temporally-resolved activity data including audio, video, EHR activity, and eye-gaze along with post-visit assessments of workload. These data are then analyzed through a combination of manual content analysis and computational techniques to temporally align streams, providing a range of process measures of EHR usage, clinical workflow, and physician-patient communication. Data was collected from primary care and specialty clinics at the Veterans Administration San Diego Healthcare System and UCSD Health, who use Electronic Health Record (EHR) platforms, CPRS and Epic, respectively. Grouping visit activity by physician, site, specialty, and patient status enables rank-ordering activity factors by their correlation to physicians' subjective work-load as captured by NASA Task Load Index survey. We developed a coding scheme that enabled us to compare timing studies between CPRS and Epic and extract patient and visit complexity profiles. We identified similar patterns of EHR use and navigation at the 2 sites despite differences in functions, user interfaces and consequent coded representations. Both sites displayed similar proportions of EHR function use and navigation, and distribution of visit length, proportion of time physicians attended to EHRs (gaze), and subjective work-load as measured by the task load survey. We found that visit activity was highly variable across individual physicians, and the observed activity metrics ranged widely as correlates to subjective workload. We discuss implications of our study for methodology, clinical workflow and EHR redesign. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Modeling Workload Impact in Multiple Unmanned Vehicle Supervisory Control

    DTIC Science & Technology

    2010-01-01

    task (e.g., replanning the path of a UV because of an emergent target). Compared to more common measures of workload (e.g., pupil dilation, NASA TLX ...utilization (p=.005). 0 5 10 15 20 25 30 35 40 45 50 W ai t t im es d ue t o at te nt io n in ef fic ie nc ie s (s ec ) Utilization (%) No

  17. [Distribution and main influential factors of mental workload of middle school teachers in Nanchang City].

    PubMed

    Xiao, Yuanmei; Li, Weijuan; Ren, Qingfeng; Ren, Xiaohui; Wang, Zhiming; Wang, Mianzhen; Lan, Yajia

    2015-01-01

    To investigate the distribution and main influential factors of mental workload of middle school teachers in Nanchang City. A total of 504 middle school teachers were sampled by random cluster sampling from middle schools in Nanchang City, and the mental workload level was assessed with National Aeronautics and Space Administration-Task Load Index (NASA-TLX) which was verified in reliability and validity. The mental workload scores of middle school teachers in Nanchang was approximately normal distribution. The mental workload level of middle school teachers aged 31 -35 years old was the highest. For those no more than 35 years old, there was positive correlation between mental workload and age (r = 0.146, P < 0.05). For those more than 35 years old, the levels of their mental workload had no statistically significant difference. There was a negative correlation between mental workload and educational level(r = -0.172, P < 0.05). The middle school teachers with lower educational level seemed to have a higher mental workload (P < 0.01). The longer a middle school teacher worked per day, the higher the mental workload was. Working hours per day was the most influential factor on mental workload in all influential factors (P < 0.001). Mental workload of middle school teachers was closely related to age, educational level and work hours per day. Working hours per day was the important risk factor of mental workload. Reducing working hours per day, especially reducing it to be no more than 8 hours per day, may be a significant and useful approach alleviating mental workload of middle school teachers in Nanchang City.

  18. Inflight workload assessment: comparison of subjective and physiological measurements.

    PubMed

    Lee, Yung-Hui; Liu, Bor-Shong

    2003-10-01

    Assessment of pilot workload during flight is an important aviation safety consideration. The aim of this study was to assess inflight pilot workload using both physiological and multidimensional subjective-ratings measurements (heart rate and NASA Task Load Index, respectively), comparing relative sensitivity during the four phases of flight: take-off, cruise, approach, and landing. Ten male pilots volunteered to participate in the trials, which took place in a Boeing 747-400 flight simulator. Electrocardiography was performed throughout the test using the portable Cardiovis ECG system. Mean heart rate (HR) and incremental heart rate (delta HR) were considered indices of physiological workload. Peak HR was observed during take-off (83.2 bpm) and landing (88.6 bpm); moreover, delta HR was also greatest (14.2 bpm and 18.8 bpm). The Task Load Index (TLX) scale revealed that mental and performance demands were essential components of workload during flight. In addition, temporal demand was an important component of workload during take-off and physical demand was significant during cruise. Analysis of correlation revealed that the delta HR is significantly related to TLX scores (r = 0.81, n = 40). Management of the individual sources of stress, which tend to become predominant during different flight phases, should be emphasized in periodic recurrent training. For example, a pilot must be trained to cope with the increased temporal stresses associated with take-off. In addition, the recommendations will be concerned with maintaining vigilance, task allocation between pilots, and inflight rest during long-haul cruise.

  19. Relationship between mental workload and musculoskeletal disorders among Alzahra Hospital nurses

    PubMed Central

    Habibi, Ehsanollah; Taheri, Mohamad Reza; Hasanzadeh, Akbar

    2015-01-01

    Background: Musculoskeletal disorders (MSDs) are a serious problem among the nursing staff. Mental workload is the major cause of MSDs among nursing staff. The aim of this study was to investigate the mental workload dimensions and their association with MSDs among nurses of Alzahra Hospital, affiliated to Isfahan University of Medical Sciences. Materials and Methods: This descriptive cross-sectional study was conducted on 247 randomly selected nurses who worked in the Alzahra Hospital in Isfahan, Iran in the summer of 2013. The Persian version of National Aeronautics and Space Administration Task Load Index (NASA-TLX) (measuring mental load) specialized questionnaire and Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) was used for data collection. Data were collected and analyzed by Pearson correlation coefficient and Spearman correlation coefficient tests in SPSS 20. Results: Pearson and Spearman correlation tests showed a significant association between the nurses’ MSDs and the dimensions of workload frustration, total workload, temporal demand, effort, and physical demand (r = 0.304, 0.277, 0.277, 0.216, and 0.211, respectively). However, there was no significant association between the nurses’ MSDs and the dimensions of workload performance and mental demand (P > 0.05). Conclusions: The nurses’ frustration had a direct correlation with MSDs. This shows that stress is an inseparable component in hospital workplace. Thus, reduction of stress in nursing workplace should be one of the main priorities of hospital managers. PMID:25709683

  20. Catastrophe models for cognitive workload and fatigue in N-back tasks.

    PubMed

    Guastello, Stephen J; Reiter, Katherine; Malon, Matthew; Timm, Paul; Shircel, Anton; Shaline, James

    2015-04-01

    N-back tasks place a heavy load on working memory, and thus make good candidates for studying cognitive workload and fatigue (CWLF). This study extended previous work on CWLF which separated the two phenomena with two cusp catastrophe models. Participants were 113 undergraduates who completed 2-back and 3-back tasks with both auditory and visual stimuli simultaneously. Task data were complemented by several measures hypothesized to be related to cognitive elasticity and compensatory abilities and the NASA TLX ratings of subjective workload. The adjusted R2 was .980 for the workload model, which indicated a highly accurate prediction with six bifurcation (elasticity versus rigidity) effects: algebra flexibility, TLX performance, effort, and frustration; and psychosocial measures of inflexibility and monitoring. There were also two cognitive load effects (asymmetry): 2 vs. 3-back and TLX temporal demands. The adjusted R2 was .454 for the fatigue model, which contained two bifurcation variables indicating the amount of work done, and algebra flexibility as the compensatory ability variable. Both cusp models were stronger than the next best linear alternative model. The study makes an important step forward by uncovering an apparently complete model for workload, finding the role of subjective workload in the context of performance dynamics, and finding CWLF dynamics in yet another type of memory-intensive task. The results were also consistent with the developing notion that performance deficits induced by workload and deficits induced by fatigue result from the impact of the task on the workspace and executive functions of working memory respectively.

  1. Upper limb muscular activity and perceived workload during laryngoscopy: comparison of Glidescope(R) and Macintosh laryngoscopy in manikin: an observational study.

    PubMed

    Caldiroli, D; Molteni, F; Sommariva, A; Frittoli, S; Guanziroli, E; Cortellazzi, P; Orena, E F

    2014-03-01

    The interaction between operators and their working environment during laryngoscopy is poorly understood. Numerous studies have focused on the forces applied to the patient's airway during laryngoscopy, but only a few authors have addressed operator muscle activity and workload. We tested whether different devices (Glidescope(®) and Macintosh) use different muscles and how these differences affect the perceived workload. Ten staff anaesthetists performed three intubations with each device on a manikin. Surface electromyography was recorded for eight single muscles of the left upper limb. The NASA Task Load Index (TLX) was administered after each experimental session to evaluate perceived workload. A consistent reduction in muscular activation occurred with Glidescope(®) compared with Macintosh for all muscles tested (mean effect size d=3.28), and significant differences for the upper trapezius (P=0.002), anterior deltoid (P=0.001), posterior deltoid (P=0.000), and brachioradialis (P=0.001) were observed. The overall NASA-TLX workload score was significantly lower for Glidescope(®) than for Macintosh (P=0.006), and the factors of physical demand (P=0.008) and effort (P=0.006) decreased significantly. Greater muscular activity and workload were observed with the Macintosh laryngoscope. Augmented vision and related postural adjustments related to using the Glidescope(®) may reduce activation of the operator's muscles and task workload.

  2. Toward a better understanding of task demands, workload, and performance during physician-computer interactions.

    PubMed

    Mazur, Lukasz M; Mosaly, Prithima R; Moore, Carlton; Comitz, Elizabeth; Yu, Fei; Falchook, Aaron D; Eblan, Michael J; Hoyle, Lesley M; Tracton, Gregg; Chera, Bhishamjit S; Marks, Lawrence B

    2016-11-01

    To assess the relationship between (1) task demands and workload, (2) task demands and performance, and (3) workload and performance, all during physician-computer interactions in a simulated environment. Two experiments were performed in 2 different electronic medical record (EMR) environments: WebCIS (n = 12) and Epic (n = 17). Each participant was instructed to complete a set of prespecified tasks on 3 routine clinical EMR-based scenarios: urinary tract infection (UTI), pneumonia (PN), and heart failure (HF). Task demands were quantified using behavioral responses (click and time analysis). At the end of each scenario, subjective workload was measured using the NASA-Task-Load Index (NASA-TLX). Physiological workload was measured using pupillary dilation and electroencephalography (EEG) data collected throughout the scenarios. Performance was quantified based on the maximum severity of omission errors. Data analysis indicated that the PN and HF scenarios were significantly more demanding than the UTI scenario for participants using WebCIS (P < .01), and that the PN scenario was significantly more demanding than the UTI and HF scenarios for participants using Epic (P < .01). In both experiments, the regression analysis indicated a significant relationship only between task demands and performance (P < .01). Results suggest that task demands as experienced by participants are related to participants' performance. Future work may support the notion that task demands could be used as a quality metric that is likely representative of performance, and perhaps patient outcomes. The present study is a reasonable next step in a systematic assessment of how task demands and workload are related to performance in EMR-evolving environments. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Effects of Visual Communication Tool and Separable Status Display on Team Performance and Subjective Workload in Air Battle Management

    DTIC Science & Technology

    2008-06-01

    NASAS TLX (Hart & Staveland, 1987) was used to evaluate perceived task demands. In the modified version, participants were asked to estimate the...subjective workload (i.e., NASA - TLX ) was assessed for each trial. Unweighted NASA - TLX ratings were submitted to a 5 (Subscale) × 2 (Communication...Communication Condition M ea n TL X R at in g Figure 3. Mean unweighted NASA - TLX ratings as a function of communication modality. Error bars represent one

  4. Mental workload measurement: Event-related potentials and ratings of workload and fatigue

    NASA Technical Reports Server (NTRS)

    Biferno, M. A.

    1985-01-01

    Event-related potentials were elicited when a digitized word representing a pilot's call-sign was presented. This auditory probe was presented during 27 workload conditions in a 3x3x3 design where the following variables were manipulated: short-term load, tracking task difficulty, and time-on-task. Ratings of workload and fatigue were obtained between each trial of a 2.5-hour test. The data of each subject were analyzed individually to determine whether significant correlations existed between subjective ratings and ERP component measures. Results indicated that a significant number of subjects had positive correlations between: (1) ratings of workload and P300 amplitude, (2) ratings of workload and N400 amplitude, and (3) ratings of fatigue and P300 amplitude. These data are the first to show correlations between ratings of workload or fatigue and ERP components thereby reinforcing their validity as measures of mental workload and fatigue.

  5. Linking Simulation with Formal Verification and Modeling of Wireless Sensor Network in TLA+

    NASA Astrophysics Data System (ADS)

    Martyna, Jerzy

    In this paper, we present the results of the simulation of a wireless sensor network based on the flooding technique and SPIN protocols. The wireless sensor network was specified and verified by means of the TLA+ specification language [1]. For a model of wireless sensor network built this way simulation was carried with the help of specially constructed software tools. The obtained results allow us to predict the behaviour of the wireless sensor network in various topologies and spatial densities. Visualization of the output data enable precise examination of some phenomenas in wireless sensor networks, such as a hidden terminal, etc.

  6. Impact of 3D vision on mental workload and laparoscopic performance in inexperienced subjects.

    PubMed

    Gómez-Gómez, E; Carrasco-Valiente, J; Valero-Rosa, J; Campos-Hernández, J P; Anglada-Curado, F J; Carazo-Carazo, J L; Font-Ugalde, P; Requena-Tapia, M J

    2015-05-01

    To assess the effect of vision in three dimensions (3D) versus two dimensions (2D) on mental workload and laparoscopic performance during simulation-based training. A prospective, randomized crossover study on inexperienced students in operative laparoscopy was conducted. Forty-six candidates executed five standardized exercises on a pelvitrainer with both vision systems (3D and 2D). Laparoscopy performance was assessed using the total time (in seconds) and the number of failed attempts. For workload assessment, the validated NASA-TLX questionnaire was administered. 3D vision improves the performance reducing the time (3D = 1006.08 ± 315.94 vs. 2D = 1309.17 ± 300.28; P < .001) and the total number of failed attempts (3D = .84 ± 1.26 vs. 2D = 1.86 ± 1.60; P < .001). For each exercise, 3D vision also shows better performance times: "transfer objects" (P = .001), "single knot" (P < .001), "clip and cut" (P < .05), and "needle guidance" (P < .001). Besides, according to the NASA-TLX results, less mental workload is experienced with the use of 3D (P < .001). However, 3D vision was associated with greater visual impairment (P < .01) and headaches (P < .05). The incorporation of 3D systems in laparoscopic training programs would facilitate the acquisition of laparoscopic skills, because they reduce mental workload and improve the performance on inexperienced surgeons. However, some undesirable effects such as visual discomfort or headache are identified initially. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. [Eighty cases of monitored anesthesia care (MAC) for inguinal hernia repairs using tumescent local anesthesia (TLA)].

    PubMed

    Adachi, Koko; Kameyama, Eri; Yamada, Masahiro; Nakamura, Tadaho; Uchida, Kentaroh; Hayasaka, Tomoko

    2011-10-01

    This paper discusses the efficacy and difficulty of the management of monitored anesthesia care (MAC) for inguinal hernia repairs using tumescent local anesthesia(TLA). Eighty patients were retrospectively divided into four groups (all n = 20) according to the drugs used; group P (propofol), group PF (propofol and fentanyl), group PFM (propofol, fentanyl and midazolam), group PR (propofol and remifentanyl). The four groups were analyzed in terms of the applied dose, airway use, wake-up test to determine whether hernia was repaired, postoperative pain and nausea. More propofol was administered in group P than in group PFM and PR. Although, airway was used for nine patients, there was no difference between the four groups. Postoperative pain and nausea also do not differ between the groups. One patient in group P showed unsuccessful repair with wake-up test. MAC shows a beneficial effect on inguinal hernia repairs under TLA. The rate of airway use was as high as eleven percent, and maintenance of the patients' airway requires attention. In terms of wake-up test, propofol combined with opioid administration may be more effective than propofol administration alone. There was no significant difference between the groups in pain and nausea, regardless at the use of fentanyl or remifentanil.

  8. Driver's mental workload prediction model based on physiological indices.

    PubMed

    Yan, Shengyuan; Tran, Cong Chi; Wei, Yingying; Habiyaremye, Jean Luc

    2017-09-15

    Developing an early warning model to predict the driver's mental workload (MWL) is critical and helpful, especially for new or less experienced drivers. The present study aims to investigate the correlation between new drivers' MWL and their work performance, regarding the number of errors. Additionally, the group method of data handling is used to establish the driver's MWL predictive model based on subjective rating (NASA task load index [NASA-TLX]) and six physiological indices. The results indicate that the NASA-TLX and the number of errors are positively correlated, and the predictive model shows the validity of the proposed model with an R 2 value of 0.745. The proposed model is expected to provide a reference value for the new drivers of their MWL by providing the physiological indices, and the driving lesson plans can be proposed to sustain an appropriate MWL as well as improve the driver's work performance.

  9. Heavy vehicle driver workload assessment. Task 4, review of workload and related research

    DOT National Transportation Integrated Search

    This report reviews literature on workload measures and related research. It depicts the preliminary development of a theoretical basis for relating driving workload to highway safety and a selective review of driver performance evaluation, workload ...

  10. Maximum Movement Workloads and High-Intensity Workload Demands by Position in NCAA Division I Collegiate Football.

    PubMed

    Sanders, Gabriel J; Roll, Brad; Peacock, Corey A; Kollock, Roger O

    2018-05-02

    Sanders, GJ, Roll, B, Peacock, CA, and Kollock, RO. Maximum movement workloads and high-intensity workload demands by position in NCAA division I collegiate football. J Strength Cond Res XX(X): 000-000, 2018-The purpose of the study was to quantify the average and maximum (i.e., peak) movement workloads, and the percent of those workloads performed at high intensity by NCAA division I football athletes during competitive games. Using global positioning system devices (Catapult Sports), low, moderate, and high and total multidirectional movement workloads were quantified by each position. Strategically achieving maximal workloads may improve both conditioning and rehabilitation protocols for athletes as they prepare for competition or return to play after an injury. A total of 40 football athletes were included in the analysis. For the data to be included, athletes were required to participate in ≥75% of the offensive or defensive snaps for any given game. There was a total of 286 data downloads from 13 different games for 8 different football positions. Data were calculated and compared by offensive and defensive position to establish the mean, SD, and maximum workloads during competitive games. The percent high-intensity workload profile was established to assess the total number and percent of high-intensity movement workloads by position. The profile was calculated by dividing a position's maximal high-intensity movement workload by the total (e.g., sum of maximal low, moderate, and high-intensity movements) movement workload. One-way analysis of variances revealed that there was a main effect of football position for total movement workloads and the percent of workloads performed at high intensities (p ≤ 0.025 for all). Maximal high-intensity workloads were 1.6-4.3 times greater than average high-intensity workloads, and the percent of total workloads performed at high intensities varied greatly by position. Strategically training for and using maximal

  11. Heavy vehicle driver workload assessment. Task 5, workload assessment protocol

    DOT National Transportation Integrated Search

    This report presents a description of a prescriptive workload assessment protocol for use in evaluating in-cab devices in heavy vehicles. The primary objective of this heavy vehicle driver workload assessment protocol is to identify the components an...

  12. The workload book: Assessment of operator workload to engineering systems

    NASA Technical Reports Server (NTRS)

    Gopher, D.

    1983-01-01

    The structure and initial work performed toward the creation of a handbook for workload analysis directed at the operational community of engineers and human factors psychologists are described. The goal, when complete, will be to make accessible to such individuals the results of theoretically-based research that are of practical interest and utility in the analysis and prediction of operator workload in advanced and existing systems. In addition, the results of laboratory study focused on the development of a subjective rating technique for workload that is based on psychophysical scaling techniques are described.

  13. Construction of a survey to assess workload and fatigue among AMT operators in Mexico.

    PubMed

    Hernández Arellano, Juan Luis; Ibarra Mejía, Gabriel; Serratos Pérez, J Nieves; García Alcaraz, Jorge Luis; Brunette, María Julia

    2012-01-01

    Operators of machinery classified as Advanced Manufacturing Technology (AMT) are exposed to high levels of workload and fatigue. However, only few studies have been conducted on this topic in Hispanic-American countries workers. Several instruments be used to assess workload and fatigue; however, only few of them have been adapted to Spanish language. This paper reports on the development and validity testing of a survey instrument in Spanish, aiming to subjectively assess workload and fatigue among AMT operators in Mexico. After an exhaustive literature review in search of already available measurement instruments, they were adapted for content and later translated into Spanish; a pilot test was conducted to evaluate validity and reliability; afterwards appropriate modifications were made to the testing instruments. Final version of the instrument was applied to a group of 121 operators of CNC lathes. Reliability was analyzed using KMO and Cronbach alpha indices. For the assessment of workload, both NASA-TLX and ISTAS 21 methods were incorporated to the survey instrument. As for fatigue assessment tools, these were SOFI-S, FAS and OFER questionnaires. RESULTS show KMO value and Cronbach alpha above 0.6.Conclusions. The survey instrument as designed, allows the collection of reliable and valid data regarding workload and fatigue among AMT operators in Mexico.

  14. Effects of work zone configurations and traffic density on performance variables and subjective workload.

    PubMed

    Shakouri, Mahmoud; Ikuma, Laura H; Aghazadeh, Fereydoun; Punniaraj, Karthy; Ishak, Sherif

    2014-10-01

    This paper investigates the effect of changing work zone configurations and traffic density on performance variables and subjective workload. Data regarding travel time, average speed, maximum percent braking force and location of lane changes were collected by using a full size driving simulator. The NASA-TLX was used to measure self-reported workload ratings during the driving task. Conventional lane merge (CLM) and joint lane merge (JLM) were modeled in a driving simulator, and thirty participants (seven female and 23 male), navigated through the two configurations with two levels of traffic density. The mean maximum braking forces was 34% lower in the JLM configuration, and drivers going through the JLM configuration remained in the closed lane longer. However, no significant differences in speed were found between the two merge configurations. The analysis of self-reported workload ratings show that participants reported 15.3% lower total workload when driving through the JLM. In conclusion, the implemented changes in the JLM make it a more favorable merge configuration in both high and low traffic densities in terms of optimizing traffic flow by increasing the time and distance cars use both lanes, and in terms of improving safety due to lower braking forces and lower reported workload. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Evaluation of the impact of a total automation system in a large core laboratory on turnaround time.

    PubMed

    Lou, Amy H; Elnenaei, Manal O; Sadek, Irene; Thompson, Shauna; Crocker, Bryan D; Nassar, Bassam

    2016-11-01

    Growing financial and workload pressures on laboratories coupled with user demands for faster turnaround time (TAT) has steered the implementation of total laboratory automation (TLA). The current study evaluates the impact of a complex TLA on core laboratory efficiency through the analysis of the In-lab to Report TAT (IR-TAT) for five representative tests based on the different requested priorities. Mean, median and outlier percentages (OP) for IR-TAT were determined following TLA implementation and where possible, compared to the pre-TLA era. The shortest mean IR-TAT via the priority lanes of the TLA was 22min for Complete Blood Count (CBC), followed by 34min, 39min and 40min for Prothrombin time (PT), urea and potassium testing respectively. The mean IR-TAT for STAT CBC loaded directly on to the analyzers was 5min shorter than that processed via the TLA. The mean IR-TATs for both STAT potassium and urea via offline centrifugation were comparable to that processed by the TLA. The longest mean IR-TAT via regular lanes of the TLA was 62min for Thyroid-Stimulating Hormone (TSH) while the shortest was 17min for CBC. All parameters for IR-TAT for CBC and PT tests decreased significantly post- TLA across all requested priorities in particular the outlier percentage (OP) at 30 and 60min. TLA helps to efficiently manage substantial volumes of samples across all requested priorities. Manual processing for small STAT volumes, at both the initial centrifugation stage and front loading directly on to analyzers, is however likely to yield the shortest IR-TAT. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  16. FMP study of pilot workload. Qualification of workload via instrument scan

    NASA Technical Reports Server (NTRS)

    Tolel, J. R.; Vivaudou, M.; Harris, R. L., Sr.; Ephrath, A.

    1982-01-01

    Various methods of measuring a pilot's mental workload are discussed. Scanning the various flight instruments with good scan pattern and other verbal tasks during instrument landings is given special attention for measuring pilot workload.

  17. Predicting operator workload during system design

    NASA Technical Reports Server (NTRS)

    Aldrich, Theodore B.; Szabo, Sandra M.

    1988-01-01

    A workload prediction methodology was developed in response to the need to measure workloads associated with operation of advanced aircraft. The application of the methodology will involve: (1) conducting mission/task analyses of critical mission segments and assigning estimates of workload for the sensory, cognitive, and psychomotor workload components of each task identified; (2) developing computer-based workload prediction models using the task analysis data; and (3) exercising the computer models to produce predictions of crew workload under varying automation and/or crew configurations. Critical issues include reliability and validity of workload predictors and selection of appropriate criterion measures.

  18. Bioinstrumentation for evaluation of workload in payload specialists: results of ASSESS II

    NASA Astrophysics Data System (ADS)

    Wegmann, Hans M.; Herrmann, Reinhold; Winget, Charles M.

    1980-11-01

    ASSESS II‡Acronym for Airborne Science/Spacelab Experiments System Simulation. was a cooperative NASA-ESA project which consisted of a detailed simulation of Spacelab operations using the NASA Ames Research Center CV-990 aircraft laboratory. The Medical Experiment reported on in this paper was part of the complex payload consisting of 11 different experiments. Its general purpose was to develop a technology, possibly flown on board of Spacelab, and enabling the assessment of workload through evaluating changes of circadian rhythmicity, sleep disturbances and episodical or cumulative stress. As parameters the following variables were measured: Rectal temperature, ECG, sleep-EEG and -EOG, the urinary excretion of hormones and electrolytes. The results revealed evidence that a Spacelab environment, as simulated in ASSESS II, will lead to internal dissociation of circadian rhythms, to sleep disturbances and to highly stressful working conditions. Altogether these effects will impose considerable workload upon Payload Specialists. It is suggested that an intensive pre-mission system simulation will reduce these impairments to a reasonable degree. The bioinstrumentation applied in this experiment proved to be a practical and reliable tool in assessing the objectives of the study.

  19. Cognitive workload changes for nurses transitioning from a legacy system with paper documentation to a commercial electronic health record.

    PubMed

    Colligan, Lacey; Potts, Henry W W; Finn, Chelsea T; Sinkin, Robert A

    2015-07-01

    Healthcare institutions worldwide are moving to electronic health records (EHRs). These transitions are particularly numerous in the US where healthcare systems are purchasing and implementing commercial EHRs to fulfill federal requirements. Despite the central role of EHRs to workflow, the cognitive impact of these transitions on the workforce has not been widely studied. This study assesses the changes in cognitive workload among pediatric nurses during data entry and retrieval tasks during transition from a hybrid electronic and paper information system to a commercial EHR. Baseline demographics and computer attitude and skills scores were obtained from 74 pediatric nurses in two wards. They also completed an established and validated instrument, the NASA-TLX, that is designed to measure cognitive workload; this instrument was used to evaluate cognitive workload of data entry and retrieval. The NASA-TLX was administered at baseline (pre-implementation), 1, 5 and 10 shifts and 4 months post-implementation of the new EHR. Most nurse participants experienced significant increases of cognitive workload at 1 and 5 shifts after "go-live". These increases abated at differing rates predicted by participants' computer attitudes scores (p = 0.01). There is substantially increased cognitive workload for nurses during the early phases (1-5 shifts) of EHR transitions. Health systems should anticipate variability across workers adapting to "meaningful use" EHRs. "One-size-fits-all" training strategies may not be suitable and longer periods of technical support may be necessary for some workers. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. NASA Task Load Index (TLX). Volume 1.0; Computerized Version

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G.

    1986-01-01

    This booklet and the accompanying diskette contain the materials necessary to collect subjective workload assessments with the NASA Task Load Index on IBM PC compatible microcomputers. This procedure for collecting workload ratings was developed by the Human Performance Group at NASA Ames Research Center during a three year research effort that involved more than 40 laboratory, simulation, and inflight experiments Although the technique is still undergoing evaluation, this package is being distributed to allow other researchers to use it in their own experiments Comments or suggestions about the procedure would be greatly appreciated This package is intended to fill a "nuts and bolts" function of describing the procedure. A bibliography provides background information about previous empirical findings and the logic that supports the procedure.

  1. School Nurse Workload.

    PubMed

    Endsley, Patricia

    2017-02-01

    The purpose of this scoping review was to survey the most recent (5 years) acute care, community health, and mental health nursing workload literature to understand themes and research avenues that may be applicable to school nursing workload research. The search for empirical and nonempirical literature was conducted using search engines such as Google Scholar, PubMed, CINAHL, and Medline. Twenty-nine empirical studies and nine nonempirical articles were selected for inclusion. Themes that emerged consistent with school nurse practice include patient classification systems, environmental factors, assistive personnel, missed nursing care, and nurse satisfaction. School nursing is a public health discipline and population studies are an inherent research priority but may overlook workload variables at the clinical level. School nurses need a consistent method of population assessment, as well as evaluation of appropriate use of assistive personnel and school environment factors. Assessment of tasks not directly related to student care and professional development must also be considered in total workload.

  2. Performance evaluation of NASA/KSC CAD/CAE graphics local area network

    NASA Technical Reports Server (NTRS)

    Zobrist, George

    1988-01-01

    This study had as an objective the performance evaluation of the existing CAD/CAE graphics network at NASA/KSC. This evaluation will also aid in projecting planned expansions, such as the Space Station project on the existing CAD/CAE network. The objectives were achieved by collecting packet traffic on the various integrated sub-networks. This included items, such as total number of packets on the various subnetworks, source/destination of packets, percent utilization of network capacity, peak traffic rates, and packet size distribution. The NASA/KSC LAN was stressed to determine the useable bandwidth of the Ethernet network and an average design station workload was used to project the increased traffic on the existing network and the planned T1 link. This performance evaluation of the network will aid the NASA/KSC network managers in planning for the integration of future workload requirements into the existing network.

  3. Workload: Measurement and Management

    NASA Technical Reports Server (NTRS)

    Gore, Brian Francis; Casner, Stephen

    2010-01-01

    Poster: The workload research project has as its task to survey the available literature on: (1) workload measurement techniques; and (2) the effects of workload on operator performance. The first set of findings provides practitioners with a collection of simple-to-use workload measurement techniques along with characterizations of the kinds of tasks each technique has been shown reliably address. This allows design practitioners to select and use the most appropriate techniques for the task(s) at hand. The second set of findings provides practitioners with the guidance they need to design for appropriate kinds and amounts of workload across all tasks for which the operator is responsible. This guidance helps practitioners design systems and procedures that ensure appropriate levels of engagement across all tasks, and avoid designs and procedures that result in operator boredom, complacency, loss of awareness, undue levels of stress, or skill atrophy that can result from workload that distracts operators from the tasks they perform and monitor, workload levels that are too low, too high, or too consistent or predictable. Only those articles that were peer reviewed, long standing and generally accepted in the field, and applicable to a relevant range of conditions in a select domain of interest, in analogous "extreme" environments to those in space were included. In addition, all articles were reviewed and evaluated on uni-dimensional and multi-dimensional considerations. Casner & Gore also examined the notion of thresholds and the conditions that may benefit mostly from the various methodological approaches. Other considerations included whether the tools would be suitable for guiding a requirement-related and design-related question. An initial review of over 225 articles was conducted and entered into an EndNote database. The reference list included a range of conditions in the domain of interest (subjective/objective measures), the seminal works in workload, as

  4. Relating physician's workload with errors during radiation therapy planning.

    PubMed

    Mazur, Lukasz M; Mosaly, Prithima R; Hoyle, Lesley M; Jones, Ellen L; Chera, Bhishamjit S; Marks, Lawrence B

    2014-01-01

    To relate subjective workload (WL) levels to errors for routine clinical tasks. Nine physicians (4 faculty and 5 residents) each performed 3 radiation therapy planning cases. The WL levels were subjectively assessed using National Aeronautics and Space Administration Task Load Index (NASA-TLX). Individual performance was assessed objectively based on the severity grade of errors. The relationship between the WL and performance was assessed via ordinal logistic regression. There was an increased rate of severity grade of errors with increasing WL (P value = .02). As the majority of the higher NASA-TLX scores, and the majority of the performance errors were in the residents, our findings are likely most pertinent to radiation oncology centers with training programs. WL levels may be an important factor contributing to errors during radiation therapy planning tasks. Published by Elsevier Inc.

  5. Supporting Academic Workloads in Online Learning

    ERIC Educational Resources Information Center

    Haggerty, Carmel E.

    2015-01-01

    Academic workloads in online learning are influenced by many variables, the complexity of which makes it difficult to measure academic workloads in isolation. While researching issues associated with academic workloads, professional development stood out as having a substantive impact on academic workloads. Many academics in applied health degrees…

  6. Defining the subjective experience of workload

    NASA Technical Reports Server (NTRS)

    Hart, S. G.; Childress, M. E.; Bortolussi, M.

    1981-01-01

    Flight scenarios that represent different types and levels of pilot workload are needed in order to conduct research about, and develop measures of, pilot workload. In order to be useful, however, the workload associated with such scenarios and the component tasks must be determined independently. An initial study designed to provide such information was conducted by asking a panel of general aviation pilots to evaluate flight-related tasks for the overall, perceptual, physical, and cognitive workload they impose. These ratings will provide the nucleus for a data base of flight-related primary tasks that have been independently rated for workload to use in workload assessment research.

  7. The workload analysis in welding workshop

    NASA Astrophysics Data System (ADS)

    Wahyuni, D.; Budiman, I.; Tryana Sembiring, M.; Sitorus, E.; Nasution, H.

    2018-03-01

    This research was conducted in welding workshop which produces doors, fences, canopies, etc., according to customer’s order. The symptoms of excessive workload were seen from the fact of employees complaint, requisition for additional employees, the lateness of completion time (there were 11 times of lateness from 28 orders, and 7 customers gave complaints). The top management of the workshop assumes that employees’ workload was still a tolerable limit. Therefore, it was required workload analysis to determine the number of employees required. The Workload was measured by using a physiological method and workload analysis. The result of this research can be utilized by the workshop for a better workload management.

  8. Temperature-controlled laminar airflow (TLA) device in the treatment of children with severe atopic eczema: Open-label, proof-of-concept study.

    PubMed

    Gore, C; Gore, R B; Fontanella, S; Haider, S; Custovic, A

    2018-05-01

    Children with severe, persistent atopic eczema (AE) have limited treatment options, often requiring systemic immunosuppression. To evaluate the effect of the temperature-controlled laminar airflow (TLA) treatment in children/adolescents with severe AE. We recruited 15 children aged 2-16 years with long-standing, severe AE and sensitization to ≥1 perennial inhalant allergen. Run-in period of 6-10 weeks (3 visits) was followed by 12-month treatment with overnight TLA (Airsonett ® , Sweden). The primary outcome was eczema severity (SCORAD-Index and Investigator Global Assessment-IGA). Secondary outcomes included child/family dermatology quality of life and family impact questionnaires (CDQLI, FDQLI, DFI), patient-oriented eczema measure (POEM), medication requirements and healthcare contacts. The study is registered as ISRCTN65865773. There was a significant reduction in AE severity ascertained by SCORAD and IGA during the 12-month intervention period (P < .001). SCORAD was reduced from a median of 34.9 [interquartile range 28.75-45.15] at Baseline to 17.2 [12.95-32.3] at the final visit, and IGA improved significantly from 4 [3-4] to 2 [1-3]. We observed a significant improvement in FDQLI (16.0 [12.25-19.0] to 12 [8-18], P = .023) and DFI (P = .011), but not CDQLI or POEM. Compared to 6-month period prior to enrolment, there was a significant reduction at six months after the start of the intervention in potent topical corticosteroids (P = .033). The exploratory cluster analysis revealed two strongly divergent patterns of response, with 9 patients classified as responders, and 6 as non-responders. Addition of TLA device to standard pharmacological treatment may be an effective add-on to the management of difficult-to-control AE. © 2018 John Wiley & Sons Ltd.

  9. Workload - An examination of the concept

    NASA Technical Reports Server (NTRS)

    Gopher, Daniel; Donchin, Emanuel

    1986-01-01

    The relations between task difficulty and workload and workload and performance are examined. The architecture and limitations of the central processor are discussed. Various procedures for measuring workload are described and evaluated. Consideration is given to normative and descriptive approaches; subjective, performance, and arousal measures; performance operating characteristics; and psychophysiological measures of workload.

  10. NASA Task Load Index (TLX). Volume 1.0; Paper and Pencil Package

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G.

    1986-01-01

    This booklet contains the materials necessary to collect subjective workload assessments with the NASA Task Load Index. This procedure for collecting workload ratings was developed by the Human Performance Group at NASA Ames Research Center during a three year research effort that involved more than 40 laboratory. simulation. and inflight experiments. Although the technique is still undergoing evaluation. this booklet is being distributed to allow other researchers to use it in their own experiments. Comments or suggestions about the procedure would be greatly appreciated. This package is intended to fill a "nuts and bolts" function of describing the procedure. A bibliography provides background information about previous empirical findings and the logic that supports the procedure.

  11. The impact of crosstalk on three-dimensional laparoscopic performance and workload.

    PubMed

    Sakata, Shinichiro; Grove, Philip M; Watson, Marcus O; Stevenson, Andrew R L

    2017-10-01

    This is the first study to explore the effects of crosstalk from 3D laparoscopic displays on technical performance and workload. We studied crosstalk at magnitudes that may have been tolerated during laparoscopic surgery. Participants were 36 voluntary doctors. To minimize floor effects, participants completed their surgery rotations, and a laparoscopic suturing course for surgical trainees. We used a counterbalanced, within-subjects design in which participants were randomly assigned to complete laparoscopic tasks in one of six unique testing sequences. In a simulation laboratory, participants were randomly assigned to complete laparoscopic 'navigation in space' and suturing tasks in three viewing conditions: 2D, 3D without ghosting and 3D with ghosting. Participants calibrated their exposure to crosstalk as the maximum level of ghosting that they could tolerate without discomfort. The Randot® Stereotest was used to verify stereoacuity. The study performance metric was time to completion. The NASA TLX was used to measure workload. Normal threshold stereoacuity (40-20 second of arc) was verified in all participants. Comparing optimal 3D with 2D viewing conditions, mean performance times were 2.8 and 1.6 times faster in laparoscopic navigation in space and suturing tasks respectively (p< .001). Comparing optimal 3D with suboptimal 3D viewing conditions, mean performance times were 2.9 times faster in both tasks (p< .001). Mean workload in 2D was 1.5 and 1.3 times greater than in optimal 3D viewing, for navigation in space and suturing tasks respectively (p< .001). Mean workload associated with suboptimal 3D was 1.3 times greater than optimal 3D in both laparoscopic tasks (p< .001). There was no significant relationship between the magnitude of ghosting score, laparoscopic performance and workload. Our findings highlight the advantages of 3D displays when used optimally, and their shortcomings when used sub-optimally, on both laparoscopic performance and workload.

  12. Measuring mental workload and physiological reactions in marine pilots: Building bridges towards redlines of performance.

    PubMed

    Orlandi, Luca; Brooks, Benjamin

    2018-05-01

    This paper investigates the effects of shiphandling manoeuvres on mental workload and physiological reactions in ten marine pilots. Each pilot performed four berthings in a ship simulator. Those berthings were differentiated by two factors, level of difficulty and familiarity with the port. Each berthing could also be divided into five phases, three during the execution and two resting periods, one before and one after the execution (dedicated to baseline physiological data collection). Mental workload was measured through two self assessment scales: the NASA TLX and a Likert scale. Power spectral densities on Beta bands 1 and 2 were obtained from EEG. Heart rate and heart rate variability were obtained from ECG. Pupil dilation was obtained from eye tracking. Workload levels were higher as berthings increased in difficulty level and/or the pilots completed the berthings in unfamiliar ports. Responses differed across specific phases of the berthings. Physiological responses could indirectly monitor levels of mental workload, and could be adopted in future applications to evaluate training improvements and performance. This study provides an example of an applied methodology aiming to define an upper redline of task demands in the context of marine pilotage. Copyright © 2018. Published by Elsevier Ltd.

  13. Using Pupil Diameter Changes for Measuring Mental Workload under Mental Processing

    NASA Astrophysics Data System (ADS)

    Batmaz, Ihsan; Ozturk, Mustafa

    In this study, it is aimed to evaluate the mental workload by using a practical way which based on measuring pupil diameter changes that occurs under mental processing. To determine the mental effort required for each task, the video record of subjects` eyes are taken while they are performed different tasks and pupils were measured from the records. A group of university student, one female 9 males participated to the experiment. Additionally, NASA-TLX questionnaire is applied for the related mental tasks. For verification of results obtained from both indices, the correlation coefficient is calculated task base. The results show that there is weak and negative correlation between the indices on task base except 3rd task. By investigating pupil diameter measurements data too, it is founded that pupil dilates under mental workload during performing related tasks. For all tasks, pupil diameters of response periods increased according to reference baseline period.

  14. Workload and Stress in New Zealand Universities.

    ERIC Educational Resources Information Center

    Boyd, Sally; Wylie, Cathy

    This study examined the workloads of academic, general, support, library, and technical staff of New Zealand universities. It focused on current levels of workload, changes in workload levels and content, connections between workload and stress, and staff attitudes towards the effects of workload changes and educational reforms on the quality of…

  15. Operator Workload: Comprehensive Review and Evaluation of Operator Workload Methodologies

    DTIC Science & Technology

    1989-06-01

    chocking for system failures or emergency conditions. It seems fair to characterize the changes In operator functions as more mental or cognitive In nature ...that the operator, the system hardware, and the evMronment all interact in affecting performance and this Interaction can change the nature of the task...a) classifying the nature of the operator tasks and (b) classifying workload assessment techniques. Task taxonomies are useful because some workload

  16. Excitation functions of heavy ion induced nuclear reactions between 16O ion beam and natural copper: Measurements, analysis and its applicability in TLA study

    NASA Astrophysics Data System (ADS)

    Chowdhury, D. P.; Guin, R.; Saha, S. K.; Sudersanan, M.

    2003-11-01

    Experimental cross sections of a number of reaction channels of 16O ion induced reactions on natural copper target have been determined at different energies in the range of 50-110 MeV of 16O projectile by stacked foil activation technique. The cross sections have been compared with theoretical calculations using the computer code ALICE-91. The experimental values compared reasonably well with the corresponding theoretical estimates. The results indicate no significant role of incomplete fusion process in the 16O induced reactions on natural copper in the energy range of ⩽7 MeV/nucleon. As heavy ion beam produces an extremely narrow layer of activities in the surface of a material, these reactions could be useful for thin layer activation (TLA) study. The purpose of this work is to apply heavy ion activation in TLA technique for the study of surface wear with increased sensitivity.

  17. A colored petri nets based workload evaluation model and its validation through Multi-Attribute Task Battery-II.

    PubMed

    Wang, Peng; Fang, Weining; Guo, Beiyuan

    2017-04-01

    This paper proposed a colored petri nets based workload evaluation model. A formal interpretation of workload was firstly introduced based on the process that reflection of petri nets components to task. A petri net based description of Multiple Resources theory was given by comprehending it from a new angle. A new application of VACP rating scales named V/A-C-P unit, and the definition of colored transitions were proposed to build a model of task process. The calculation of workload mainly has the following four steps: determine token's initial position and values; calculate the weight of directed arcs on the basis of the rules proposed; calculate workload from different transitions, and correct the influence of repetitive behaviors. Verify experiments were carried out based on Multi-Attribute Task Battery-II software. Our results show that there is a strong correlation between the model values and NASA -Task Load Index scores (r=0.9513). In addition, this method can also distinguish behavior characteristics between different people. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. The effects of workload on respiratory variables in simulated flight: a preliminary study.

    PubMed

    Karavidas, Maria Katsamanis; Lehrer, Paul M; Lu, Shou-En; Vaschillo, Evgeny; Vaschillo, Bronya; Cheng, Andrew

    2010-04-01

    In this pilot study, we investigated respiratory activity and end-tidal carbon dioxide (P(et)CO(2)) during exposure to varying levels of work load in a simulated flight environment. Seven pilots (age: 34-60) participated in a one-session test on the Boeing 737-800 simulator. Physiological data were collected while pilots wore an ambulatory multi-channel recording device. Respiratory variables, including inductance plethysmography (respiratory pattern) and pressure of end-tidal carbon dioxide (P(et)CO(2)), were collected demonstrating change in CO(2) levels proportional to changes in flight task workload. Pilots performed a set of simulation flight tasks. Pilot performance was rated for each task by a test pilot; and self-report of workload was taken using the NASA-TLX scale. Mixed model analysis revealed that respiration rate and minute ventilation are significantly associated with workload levels and evaluator scores controlling for "vanilla baseline" condition. Hypocapnia exclusively occurred in tasks where pilots performed more poorly. This study was designed as a preliminary investigation in order to develop a psychophysiological assessment methodology, rather than to offer conclusive findings. The results show that the respiratory system is very reactive to high workload conditions in aviation and suggest that hypocapnia may pose a flight safety risk under some circumstances. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. A user-oriented synthetic workload generator

    NASA Technical Reports Server (NTRS)

    Kao, Wei-Lun

    1991-01-01

    A user oriented synthetic workload generator that simulates users' file access behavior based on real workload characterization is described. The model for this workload generator is user oriented and job specific, represents file I/O operations at the system call level, allows general distributions for the usage measures, and assumes independence in the file I/O operation stream. The workload generator consists of three parts which handle specification of distributions, creation of an initial file system, and selection and execution of file I/O operations. Experiments on SUN NFS are shown to demonstrate the usage of the workload generator.

  20. Memory and subjective workload assessment

    NASA Technical Reports Server (NTRS)

    Staveland, L.; Hart, S.; Yeh, Y. Y.

    1986-01-01

    Recent research suggested subjective introspection of workload is not based upon specific retrieval of information from long term memory, and only reflects the average workload that is imposed upon the human operator by a particular task. These findings are based upon global ratings of workload for the overall task, suggesting that subjective ratings are limited in ability to retrieve specific details of a task from long term memory. To clarify the limits memory imposes on subjective workload assessment, the difficulty of task segments was varied and the workload of specified segments was retrospectively rated. The ratings were retrospectively collected on the manipulations of three levels of segment difficulty. Subjects were assigned to one of two memory groups. In the Before group, subjects knew before performing a block of trials which segment to rate. In the After group, subjects did not know which segment to rate until after performing the block of trials. The subjective ratings, RTs (reaction times) and MTs (movement times) were compared within group, and between group differences. Performance measures and subjective evaluations of workload reflected the experimental manipulations. Subjects were sensitive to different difficulty levels, and recalled the average workload of task components. Cueing did not appear to help recall, and memory group differences possibly reflected variations in the groups of subjects, or an additional memory task.

  1. The Effect of an Electronic Checklist on Critical Care Provider Workload, Errors, and Performance.

    PubMed

    Thongprayoon, Charat; Harrison, Andrew M; O'Horo, John C; Berrios, Ronaldo A Sevilla; Pickering, Brian W; Herasevich, Vitaly

    2016-03-01

    The strategy used to improve effective checklist use in intensive care unit (ICU) setting is essential for checklist success. This study aimed to test the hypothesis that an electronic checklist could reduce ICU provider workload, errors, and time to checklist completion, as compared to a paper checklist. This was a simulation-based study conducted at an academic tertiary hospital. All participants completed checklists for 6 ICU patients: 3 using an electronic checklist and 3 using an identical paper checklist. In both scenarios, participants had full access to the existing electronic medical record system. The outcomes measured were workload (defined using the National Aeronautics and Space Association task load index [NASA-TLX]), the number of checklist errors, and time to checklist completion. Two independent clinician reviewers, blinded to participant results, served as the reference standard for checklist error calculation. Twenty-one ICU providers participated in this study. This resulted in the generation of 63 simulated electronic checklists and 63 simulated paper checklists. The median NASA-TLX score was 39 for the electronic checklist and 50 for the paper checklist (P = .005). The median number of checklist errors for the electronic checklist was 5, while the median number of checklist errors for the paper checklist was 8 (P = .003). The time to checklist completion was not significantly different between the 2 checklist formats (P = .76). The electronic checklist significantly reduced provider workload and errors without any measurable difference in the amount of time required for checklist completion. This demonstrates that electronic checklists are feasible and desirable in the ICU setting. © The Author(s) 2014.

  2. Brain-wave measures of workload in advanced cockpits: The transition of technology from laboratory to cockpit simulator, phase 2

    NASA Technical Reports Server (NTRS)

    Horst, Richard L.; Mahaffey, David L.; Munson, Robert C.

    1989-01-01

    The present Phase 2 small business innovation research study was designed to address issues related to scalp-recorded event-related potential (ERP) indices of mental workload and to transition this technology from the laboratory to cockpit simulator environments for use as a systems engineering tool. The project involved five main tasks: (1) Two laboratory studies confirmed the generality of the ERP indices of workload obtained in the Phase 1 study and revealed two additional ERP components related to workload. (2) A task analysis' of flight scenarios and pilot tasks in the Advanced Concepts Flight Simulator (ACFS) defined cockpit events (i.e., displays, messages, alarms) that would be expected to elicit ERPs related to workload. (3) Software was developed to support ERP data analysis. An existing ARD-proprietary package of ERP data analysis routines was upgraded, new graphics routines were developed to enhance interactive data analysis, and routines were developed to compare alternative single-trial analysis techniques using simulated ERP data. (4) Working in conjunction with NASA Langley research scientists and simulator engineers, preparations were made for an ACFS validation study of ERP measures of workload. (5) A design specification was developed for a general purpose, computerized, workload assessment system that can function in simulators such as the ACFS.

  3. Evaluation of Electronic Formats of the NASA Task Load Index

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.

    2011-01-01

    Paper questionnaires are being replaced by electronic questionnaires. The primary objective of this research was to determine whether electronic formats of paper questionnaires change subjects ratings and, if so, how the ratings changed. Results indicated that there were no statistically significant differences in self-assessment of workload when using the electronic replica or the paper format of the NASA-TLX scale. Variations of the electronic formats were tested to enforce structure to the TLX scale. Respondents had more consistent ratings with these alternative formats of the NASA-TLX. Non-pilots, in general, had lower workload ratings than pilots. The time to input the rating was the fastest for the electronic facsimile and random title formats. Also subjects preferred the electronic formats and thought these formats were easier to use. Therefore, moving questionnaires from paper to electronic media could change respondents' answers.

  4. Laparoendoscopic single site (LESS) in vivo suturing using a magnetic anchoring and guidance system (MAGS) camera in a porcine model: impact on ergonomics and workload.

    PubMed

    Yin, Gang; Han, Woong Kyu; Faddegon, Stephen; Tan, Yung Khan; Liu, Zhuo-Wei; Olweny, Ephrem O; Scott, Daniel J; Cadeddu, Jeffrey A

    2013-01-01

    To compare the ergonomics and workload of the surgeon during single-site suturing while using the magnetic anchoring and guidance system (MAGS) camera vs a conventional laparoscope. Seven urologic surgeons were enrolled and divided into an expert group (n=2) and a novice group (n=5) according to their laparoendoscopic single-site (LESS) experience. Each surgeon performed 2 conventional LESS and 2 MAGS camera-assisted LESS vesicostomy closures in a porcine model. A Likert scale (scoring 1-5) questionnaire assessing workload, ergonomics, technical difficulty, visualization, and needle handling, as well as a validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire were used to evaluate the tasks and workloads. MAGS LESS suturing was universally favored by expert and novice surgeons compared with conventional LESS in workload (3.4 vs 4.2), ergonomics (3.4 vs 4.4), technical challenge (3.3 vs 4.3), visualization (2.4 vs 3.3), and needle handling (3.1 vs 3.9 respectively; P<.05 for all categories). Surgeon NASA-TLX assessments found MAGS LESS suturing significantly decreased the workload in physical demand (P=.004), temporal demand (P=.017), and effort (P=.006). External instrument clashing was significantly reduced in MAGS LESS suturing (P<.001). The total operative time of MAGS LESS suturing was comparable to that of conventional LESS (P=.89). MAGS camera technology significantly decreased surgeon workload and improved ergonomics. Nevertheless, LESS suturing and knot tying remains a challenging task that requires training, regardless of which camera is used. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Preliminary study of the pilot's workload during emergency procedures in helicopters air operations.

    PubMed

    Bezerra, Flávio G V; Ribeiro, Selma L O

    2012-01-01

    Military air operations and law enforcement operations in helicopters are examples of activities that require high performance of the operator. This article aimed at presenting a preliminary analysis of data obtained in the initial study in order to validate the instruments and the research protocol that focuses on the analysis of the workload imposed on helicopter pilots in emergency situations. The research was conducted in an environment of real flight training and used the NASA-TLX Scale to assess the workload and an interview guide to obtain reports on the main tasks performed. Preliminary data obtained is related to the participation of 10 (ten) volunteer pilots with experience in different types of helicopters. Four scenarios involving helicopter emergency procedures of HB-350 "Squirrel" were outlined. For this article, the analysis used only the data regarding the Physical and Mental Demands of the NASA-TLX Scale. Preliminarily, the results indicate that the "time pressure" as a factor contributing to increase mental requirement in emergency situations in flight, and that this increase was reflected in the request of mental processes such as: identification of the breakdown, attention and monitoring parameters. Future steps include extending the sample and adding physiological tools to better understand the effects of these types of emergencies on pilot performance and flight safety.

  6. Comparing the Workload Perceptions of Identifying Patient Condition and Priorities of Care Among Burn Providers in Three Burn ICUs.

    PubMed

    McInnis, Ian; Murray, Sarah J; Serio-Melvin, Maria; Aden, James K; Mann-Salinas, Elizabeth; Chung, Kevin K; Huzar, Todd; Wolf, Steven; Nemeth, Christopher; Pamplin, Jeremy C

    Multidisciplinary rounds (MDRs) in the burn intensive care unit serve as an efficient means for clinicians to assess patient status and establish patient care priorities. Both tasks require significant cognitive work, the magnitude of which is relevant because increased cognitive work of task completion has been associated with increased error rates. We sought to quantify this workload during MDR using the National Aeronautics and Space Administration Task Load Index (NASA-TLX). Research staff at three academic regional referral burn centers administered the NASA-TLX to clinicians during MDR. Clinicians assessed their workload associated with 1) "Identify(ing) if the patient is better, same, or worse than yesterday" and 2) "Identify(ing) the most important objectives of care for the patient today." Data were collected on clinician type, years of experience, and hours of direct patient care. Surveys were administered to 116 total clinicians, 41 physicians, 25 nurses, 13 medical students, and 37 clinicians in other roles. Clinicians with less experience reported more cognitive work when completing both tasks (P < .005). Clinicians in the "others" group (respiratory therapists, dieticians, pharmacists, etc.) reported less cognitive work than all other groups for both tasks (P < .05). The NASA-TLX was an effective tool for collecting perceptions of cognitive workload associated with MDR. Perceived cognitive work varied by clinician type and experience level when completing two key tasks. Less experience was associated with increased perceived work, potentially increasing mental error rates, and increasing risk to patients. Creating tools or work processes to reduce cognitive work may improve clinician performance.

  7. Subjective responses of mental workload during real time driving: A pilot field study

    NASA Astrophysics Data System (ADS)

    Rahman, N. I. A.; Dawal, S. Z. M.; Yusoff, N.

    2017-06-01

    This study evaluated drivers’ mental workload in real time driving to identify the driving situation’s complexity influences in an attempt to further design on a complete experimental study. Three driving settings were prepared: Session A (simple situation); Session B (moderately complex situation); Session C (very complex situation). To determine the mental workload, the NASA-Task Load Index (TLX) was administered to four drivers after each experimental driving session. The results showed that the Own Performance (OP) was the highest for session A (highway), while Physical Demand (PD) recorded the highest mean workload score across the session B (rural road) and C (city road). Based on the overall results of the study, it can be concluded that the highway is less demanding compared to rural and city road. It can be highlighted in this study that in the rural and city road driving situation, the timing must be set correctly to assure the relevant traffic density. Thus, the sensitivity of the timing must be considered in the future experiment. A larger number of experience drivers must be used in evaluating the driving situations to provide results that can be used to draw more realistic experiments and conclusions.

  8. Evaluating stereoscopic displays: both efficiency measures and perceived workload sensitive to manipulations in binocular disparity

    NASA Astrophysics Data System (ADS)

    van Beurden, Maurice H. P. H.; Ijsselsteijn, Wijnand A.; de Kort, Yvonne A. W.

    2011-03-01

    Stereoscopic displays are known to offer a number of key advantages in visualizing complex 3D structures or datasets. The large majority of studies that focus on evaluating stereoscopic displays for professional applications use completion time and/or the percentage of correct answers to measure potential performance advantages. However, completion time and accuracy may not fully reflect all the benefits of stereoscopic displays. In this paper, we argue that perceived workload is an additional valuable indicator reflecting the extent to which users can benefit from using stereoscopic displays. We performed an experiment in which participants were asked to perform a visual path-tracing task within a convoluted 3D wireframe structure, varying in level of complexity of the visualised structure and level of disparity of the visualisation. The results showed that an optimal performance (completion time, accuracy and workload), depend both on task difficulty and disparity level. Stereoscopic disparity revealed a faster and more accurate task performance, whereas we observed a trend that performance on difficult tasks stands to benefit more from higher levels of disparity than performance on easy tasks. Perceived workload (as measured using the NASA-TLX) showed a similar response pattern, providing evidence that perceived workload is sensitive to variations in disparity as well as task difficulty. This suggests that perceived workload could be a useful concept, in addition to standard performance indicators, in characterising and measuring human performance advantages when using stereoscopic displays.

  9. Accumulated workloads and the acute:chronic workload ratio relate to injury risk in elite youth football players

    PubMed Central

    Bowen, Laura; Gross, Aleksander Stefan; Gimpel, Mo; Li, François-Xavier

    2017-01-01

    Aim The purpose of this study was to investigate the relationship between physical workload and injury risk in elite youth football players. Methods The workload data and injury incidence of 32 players were monitored throughout 2 seasons. Multiple regression was used to compare cumulative (1, 2, 3 and 4-weekly) loads and acute:chronic (A:C) workload ratios (acute workload divided by chronic workload) between injured and non-injured players for specific GPS and accelerometer-derived variables:total distance (TD), high-speed distance (HSD), accelerations (ACC) and total load. Workloads were classified into discrete ranges by z-scores and the relative risk was determined. Results A very high number of ACC (≥9254) over 3 weeks was associated with the highest significant overall (relative risk (RR)=3.84) and non-contact injury risk (RR=5.11). Non-contact injury risk was significantly increased when a high acute HSD was combined with low chronic HSD (RR=2.55), but not with high chronic HSD (RR=0.47). Contact injury risk was greatest when A:C TD and ACC ratios were very high (1.76 and 1.77, respectively) (RR=4.98). Conclusions In general, higher accumulated and acute workloads were associated with a greater injury risk. However, progressive increases in chronic workload may develop the players' physical tolerance to higher acute loads and resilience to injury risk. PMID:27450360

  10. Nursing performance under high workload: a diary study on the moderating role of selection, optimization and compensation strategies.

    PubMed

    Baethge, Anja; Müller, Andreas; Rigotti, Thomas

    2016-03-01

    The aim of this study was to investigate whether selective optimization with compensation constitutes an individualized action strategy for nurses wanting to maintain job performance under high workload. High workload is a major threat to healthcare quality and performance. Selective optimization with compensation is considered to enhance the efficient use of intra-individual resources and, therefore, is expected to act as a buffer against the negative effects of high workload. The study applied a diary design. Over five consecutive workday shifts, self-report data on workload was collected at three randomized occasions during each shift. Self-reported job performance was assessed in the evening. Self-reported selective optimization with compensation was assessed prior to the diary reporting. Data were collected in 2010. Overall, 136 nurses from 10 German hospitals participated. Selective optimization with compensation was assessed with a nine-item scale that was specifically developed for nursing. The NASA-TLX scale indicating the pace of task accomplishment was used to measure workload. Job performance was assessed with one item each concerning performance quality and forgetting of intentions. There was a weaker negative association between workload and both indicators of job performance in nurses with a high level of selective optimization with compensation, compared with nurses with a low level. Considering the separate strategies, selection and compensation turned out to be effective. The use of selective optimization with compensation is conducive to nurses' job performance under high workload levels. This finding is in line with calls to empower nurses' individual decision-making. © 2015 John Wiley & Sons Ltd.

  11. Reconsidering the conceptualization of nursing workload: literature review.

    PubMed

    Morris, Roisin; MacNeela, Padraig; Scott, Anne; Treacy, Pearl; Hyde, Abbey

    2007-03-01

    This paper reports a literature review that aimed to analyse the way in which nursing intensity and patient dependency have been considered to be conceptually similar to nursing workload, and to propose a model to show how these concepts actually differ in both theoretical and practical terms. The literature on nursing workload considers the concepts of patient 'dependency' and nursing 'intensity' in the realm of nursing workload. These concepts differ by definition but are used to measure the same phenomenon, i.e. nursing workload. The literature search was undertaken in 2004 using electronic databases, reference lists and other available literature. Papers were sourced from the Medline, Psychlit, CINAHL and Cochrane databases and through the general search engine Google. The keywords focussed on nursing workload, nursing intensity and patient dependency. Nursing work and workload concepts and labels are defined and measured in different and often contradictory ways. It is vitally important to understand these differences when using such conceptualizations to measure nursing workload. A preliminary model is put forward to clarify the relationships between nursing workload concepts. In presenting a preliminary model of nursing workload, it is hoped that nursing workload might be better understood so that it becomes more visible and recognizable. Increasing the visibility of nursing workload should have a positive impact on nursing workload management and on the provision of patient care.

  12. A Study on the Validity of a Task Complexity Measure for Emergency Operating Procedures of Nuclear Power Plants—Comparing With a Subjective Workload

    NASA Astrophysics Data System (ADS)

    Park, J.; Jung, W.

    2006-10-01

    In this study, the appropriateness of the task complexity (TACOM) measure that can quantify the complexity of emergency tasks was investigated by comparing subjective workload scores with the associated TACOM scores. To this end, based on the NASA-TLX (task load index) technique, 18 operators were asked to subjectively estimate perceived workload for 23 emergency tasks that were specified in the emergency operating procedures of the reference nuclear power plants. As the result of comparisons, it was observed that subjective workload scores increase in proportion to the increase of TACOM scores. Therefore, it is expect that the TACOM measure can be used as a serviceable method to quantify the complexity of emergency tasks

  13. Dual Frequency Head Maps: A New Method for Indexing Mental Workload Continuously during Execution of Cognitive Tasks

    PubMed Central

    Radüntz, Thea

    2017-01-01

    One goal of advanced information and communication technology is to simplify work. However, there is growing consensus regarding the negative consequences of inappropriate workload on employee's health and the safety of persons. In order to develop a method for continuous mental workload monitoring, we implemented a task battery consisting of cognitive tasks with diverse levels of complexity and difficulty. We conducted experiments and registered the electroencephalogram (EEG), performance data, and the NASA-TLX questionnaire from 54 people. Analysis of the EEG spectra demonstrates an increase of the frontal theta band power and a decrease of the parietal alpha band power, both under increasing task difficulty level. Based on these findings we implemented a new method for monitoring mental workload, the so-called Dual Frequency Head Maps (DFHM) that are classified by support vectors machines (SVMs) in three different workload levels. The results are in accordance with the expected difficulty levels arising from the requirements of the tasks on the executive functions. Furthermore, this article includes an empirical validation of the new method on a secondary subset with new subjects and one additional new task without any adjustment of the classifiers. Hence, the main advantage of the proposed method compared with the existing solutions is that it provides an automatic, continuous classification of the mental workload state without any need for retraining the classifier—neither for new subjects nor for new tasks. The continuous workload monitoring can help ensure good working conditions, maintain a good level of performance, and simultaneously preserve a good state of health. PMID:29276490

  14. Mental workload and motor performance dynamics during practice of reaching movements under various levels of task difficulty.

    PubMed

    Shuggi, Isabelle M; Oh, Hyuk; Shewokis, Patricia A; Gentili, Rodolphe J

    2017-09-30

    The assessment of mental workload can inform attentional resource allocation during task performance that is essential for understanding the underlying principles of human cognitive-motor behavior. While many studies have focused on mental workload in relation to human performance, a modest body of work has examined it in a motor practice/learning context without considering individual variability. Thus, this work aimed to examine mental workload by employing the NASA TLX as well as the changes in motor performance resulting from the practice of a novel reaching task. Two groups of participants practiced a reaching task at a high and low nominal difficulty during which a group-level analysis assessed the mental workload, motor performance and motor improvement dynamics. A secondary cluster analysis was also conducted to identify specific individual patterns of cognitive-motor responses. Overall, both group- and cluster-level analyses revealed that: (i) all participants improved their performance throughout motor practice, and (ii) an increase in mental workload was associated with a reduction of the quality of motor performance along with a slower rate of motor improvement. The results are discussed in the context of the optimal challenge point framework and in particular it is proposed that under the experimental conditions employed here, functional task difficulty: (i) would possibly depend on an individuals' information processing capabilities, and (ii) could be indexed by the level of mental workload which, when excessively heightened can decrease the quality of performance and more generally result in delayed motor improvements. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. Pilot Workload and Speech Analysis: A Preliminary Investigation

    NASA Technical Reports Server (NTRS)

    Bittner, Rachel M.; Begault, Durand R.; Christopher, Bonny R.

    2013-01-01

    Prior research has questioned the effectiveness of speech analysis to measure the stress, workload, truthfulness, or emotional state of a talker. The question remains regarding the utility of speech analysis for restricted vocabularies such as those used in aviation communications. A part-task experiment was conducted in which participants performed Air Traffic Control read-backs in different workload environments. Participant's subjective workload and the speech qualities of fundamental frequency (F0) and articulation rate were evaluated. A significant increase in subjective workload rating was found for high workload segments. F0 was found to be significantly higher during high workload while articulation rates were found to be significantly slower. No correlation was found to exist between subjective workload and F0 or articulation rate.

  16. Cognitive demands and the relationship between age and workload in apron control.

    PubMed

    Müller, Andreas; Petru, Raluca; Angerer, Peter

    2011-01-01

    Apron controllers (ACs) determine the taxiways for aircraft entering the apron area until they reach their parking positions and vice versa. The aims of this study were to identify age-sensitive job requirements of apron control (Study 1), and to investigate the relationship between age of ACs and their workload (Study 2). Study 1: There were 14 experienced ACs who assessed the job requirements of apron control with the Fleishman-Job Analyses Survey. Additionally, during one shift, the number of parallel processed traffic data sets (indicating memory-load) and the number of delivered radio messages (indicating processing speed requirements) were assessed. Study 2: There were 30 ACs (age: 23-51 yr) who volunteered for trials during late shifts at an international airport. ACs assessed their subjective workload (NASA-Task Load Index) at four times during the shift and carried out an attention test (d2) before and after the shift. Moreover, their heart rate was assessed during the shift and in a reference period. Study 1: Results indicate that apron control requires especially high levels of memory-load and processing speed. Study 2: Hierarchical regression analyses revealed a u-shaped relationship between age and subjective workload (beta = 0.59) as well as heart rate (beta = 0.33). Up to the age of about 35-37 yr, workload and heart rate decreased with age, but afterwards the relationship became positive. There was no association between chronological age and attention performance. There is a need for age adequate job design in apron control that should especially aim at the reduction of memory-load and processing speed.

  17. Physical and mental workload in single-incision laparoscopic surgery and conventional laparoscopy.

    PubMed

    Koca, Dilek; Yıldız, Sedat; Soyupek, Feray; Günyeli, İlker; Erdemoglu, Ebru; Soyupek, Sedat; Erdemoglu, Evrim

    2015-06-01

    The aim of the present study is to evaluate mental workload and fatigue in fingers, hand, arm, shoulder in single-incision laparoscopic surgery (SILS) and multiport laparoscopy. Volunteers performed chosen tasks by standard laparoscopy and SILS. Time to complete tasks and finger and hand strength were evaluated. Lateral, tripod, and pulp pinch strengths were measured. Hand dexterity was determined by pegboard. Electromyography recordings were taken from biceps and deltoid muscles of both extremities. The main outcome measurement was median frequency (MF) slope. NASA-TLX was used for mental workload. Time to complete laparoscopic tasks were longer in the SILS group (P < .05). Decrease of strength in fingers and hand were similar in SILS and standard laparoscopy. Pegboard time was increased in both hands after SILS (P < .05). MF slope of biceps muscle and deltoid muscle in SILS was far away from the reference slope. MF slope of biceps muscle and deltoid muscle in standard laparoscopy was close to reference slope, indicating there was more fatigue in biceps and deltoid muscles of both upper extremities in SILS group. NASA-TLX score was 73 ± 13.3 and 42 ± 19.5 in SILS and multiport laparoscopy, respectively (P < .01). Mental demand, physical demand, temporal demand, performance, effort, and frustration were, respectively, scored 10.7 ± 3.8, 11.7 ± 3.5, 12.2 ± 2.7, 11 ± 3, 13.6 ± 2.7, and 13.5 ± 2.8 in SILS and 6.3 ± 3.1, 6.6 ± 3.3, 7.3 ± 3.3, 7.1 ± 4.1, 7.9 ± 3.9, and 6.6 ± 3.8 in standard laparoscopy (P < .01). SILS is mentally and physically demanding, particularly on arms and shoulders. Fatigue of big muscles, effort, and frustration were major challenges of SILS. Ergonomic intervention of instruments are needed to decrease mental and physical workload. © The Author(s) 2014.

  18. Patient Safety Incidents and Nursing Workload 1

    PubMed Central

    Carlesi, Katya Cuadros; Padilha, Kátia Grillo; Toffoletto, Maria Cecília; Henriquez-Roldán, Carlos; Juan, Monica Andrea Canales

    2017-01-01

    ABSTRACT Objective: to identify the relationship between the workload of the nursing team and the occurrence of patient safety incidents linked to nursing care in a public hospital in Chile. Method: quantitative, analytical, cross-sectional research through review of medical records. The estimation of workload in Intensive Care Units (ICUs) was performed using the Therapeutic Interventions Scoring System (TISS-28) and for the other services, we used the nurse/patient and nursing assistant/patient ratios. Descriptive univariate and multivariate analysis were performed. For the multivariate analysis we used principal component analysis and Pearson correlation. Results: 879 post-discharge clinical records and the workload of 85 nurses and 157 nursing assistants were analyzed. The overall incident rate was 71.1%. It was found a high positive correlation between variables workload (r = 0.9611 to r = 0.9919) and rate of falls (r = 0.8770). The medication error rates, mechanical containment incidents and self-removal of invasive devices were not correlated with the workload. Conclusions: the workload was high in all units except the intermediate care unit. Only the rate of falls was associated with the workload. PMID:28403334

  19. Pupillometric measurement of operator workload

    NASA Technical Reports Server (NTRS)

    Beatty, J.

    1981-01-01

    Pupillometry as a method of measuring workload is described. Pupillometric measures provide an indication of momentary fluctuations in central nervous system excitability that occur as cognitive operations are performed; the magnitude of these changes may serve as a sensitive indicator of the workload imposed by cognitive tasks.

  20. Personnel's health surveillance at work: effect of age, body mass index, and shift work on mental workload and work ability index.

    PubMed

    Safari, Shahram; Akbari, Jafar; Kazemi, Meghdad; Mououdi, Mohammad Amin; Mahaki, Behzad

    2013-01-01

    Two great changes in developed countries are taking place: populations are ageing and becoming increasingly overweight. Combination of these factors with shift work is a risk factor for work ability and mental workload that are dynamic processes which change greatly throughout an individual's work life. The aim of this study was to investigate mental workload and work ability in textile workers and to identify factors which affect work ability and mental workload. This cross-sectional study was carried out among 194 male workers in textile industry. Employees based on their job group and work conditions have been divided into 6 categories. They completed work ability index and mental workload questionnaires during three work shifts. Body mass index (BMI) and demographic details were recorded. All of the participants rated their work ability as moderate with high mental workload. The mean WAI and mental workload in age group were significant. The mean BMI was 25.5 kg/m(2) (standard deviation 4.1) and the mean age was 40.22 years. There was a statistically significant correlation between work ability index and shift work. Unlike the previous study, a decrease point in WAI started in early age that may be due to life-style work and another psychological factor; on the other hand, NASA-TLX revealed high score in six subscales that can be another reason for low WAI.

  1. Combining Quick-Turnaround and Batch Workloads at Scale

    NASA Technical Reports Server (NTRS)

    Matthews, Gregory A.

    2012-01-01

    NAS uses PBS Professional to schedule and manage the workload on Pleiades, an 11,000+ node 1B cluster. At this scale the user experience for quick-turnaround jobs can degrade, which led NAS initially to set up two separate PBS servers, each dedicated to a particular workload. Recently we have employed PBS hooks and scheduler modifications to merge these workloads together under one PBS server, delivering sub-1-minute start times for the quick-turnaround workload, and enabling dynamic management of the resources set aside for that workload.

  2. Crew workload strategies in advanced cockpits

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G.

    1990-01-01

    Many methods of measuring and predicting operator workload have been developed that provide useful information in the design, evaluation, and operation of complex systems and which aid in developing models of human attention and performance. However, the relationships between such measures, imposed task demands, and measures of performance remain complex and even contradictory. It appears that we have ignored an important factor: people do not passively translate task demands into performance. Rather, they actively manage their time, resources, and effort to achieve an acceptable level of performance while maintaining a comfortable level of workload. While such adaptive, creative, and strategic behaviors are the primary reason that human operators remain an essential component of all advanced man-machine systems, they also result in individual differences in the way people respond to the same task demands and inconsistent relationships among measures. Finally, we are able to measure workload and performance, but interpreting such measures remains difficult; it is still not clear how much workload is too much or too little nor the consequences of suboptimal workload on system performance and the mental, physical, and emotional well-being of the human operators. The rationale and philosophy of a program of research developed to address these issues will be reviewed and contrasted to traditional methods of defining, measuring, and predicting human operator workload. Viewgraphs are given.

  3. Automated clustering-based workload characterization

    NASA Technical Reports Server (NTRS)

    Pentakalos, Odysseas I.; Menasce, Daniel A.; Yesha, Yelena

    1996-01-01

    The demands placed on the mass storage systems at various federal agencies and national laboratories are continuously increasing in intensity. This forces system managers to constantly monitor the system, evaluate the demand placed on it, and tune it appropriately using either heuristics based on experience or analytic models. Performance models require an accurate workload characterization. This can be a laborious and time consuming process. It became evident from our experience that a tool is necessary to automate the workload characterization process. This paper presents the design and discusses the implementation of a tool for workload characterization of mass storage systems. The main features of the tool discussed here are: (1)Automatic support for peak-period determination. Histograms of system activity are generated and presented to the user for peak-period determination; (2) Automatic clustering analysis. The data collected from the mass storage system logs is clustered using clustering algorithms and tightness measures to limit the number of generated clusters; (3) Reporting of varied file statistics. The tool computes several statistics on file sizes such as average, standard deviation, minimum, maximum, frequency, as well as average transfer time. These statistics are given on a per cluster basis; (4) Portability. The tool can easily be used to characterize the workload in mass storage systems of different vendors. The user needs to specify through a simple log description language how the a specific log should be interpreted. The rest of this paper is organized as follows. Section two presents basic concepts in workload characterization as they apply to mass storage systems. Section three describes clustering algorithms and tightness measures. The following section presents the architecture of the tool. Section five presents some results of workload characterization using the tool.Finally, section six presents some concluding remarks.

  4. The Independence and Interdependence of Coacting Observers in Regard to Performance Efficiency, Workload, and Stress in a Vigilance Task.

    PubMed

    Funke, Gregory J; Warm, Joel S; Baldwin, Carryl L; Garcia, Andre; Funke, Matthew E; Dillard, Michael B; Finomore, Victor S; Matthews, Gerald; Greenlee, Eric T

    2016-09-01

    We investigated performance, workload, and stress in groups of paired observers who performed a vigilance task in a coactive (independent) manner. Previous studies have demonstrated that groups of coactive observers detect more signals in a vigilance task than observers working alone. Therefore, the use of such groups might be effective in enhancing signal detection in operational situations. However, concern over appearing less competent than one's cohort might induce elevated levels of workload and stress in coactive group members and thereby undermine group performance benefits. Accordingly, we performed the initial experiment comparing workload and stress in observers who performed a vigilance task coactively with those of observers who performed the vigilance task alone. Observers monitored a video display for collision flight paths in a simulated unmanned aerial vehicle control task. Self-reports of workload and stress were secured via the NASA-Task Load Index and the Dundee Stress State Questionnaire, respectively. Groups of coactive observers detected significantly more signals than did single observers. Coacting observers did not differ significantly from those operating by themselves in terms of workload but did in regard to stress; posttask distress was significantly lower for coacting than for single observers. Performing a visual vigilance task in a coactive manner with another observer does not elevate workload above that of observers working alone and serves to attenuate the stress associated with vigilance task performance. The use of coacting observers could be an effective vehicle for enhancing performance efficiency in operational vigilance. © 2016, Human Factors and Ergonomics Society.

  5. A Model of Student Workload

    ERIC Educational Resources Information Center

    Bowyer, Kyle

    2012-01-01

    Student workload is a contributing factor to students deciding to withdraw from their study before completion of the course, at significant cost to students, institutions and society. The aim of this paper is to create a basic workload model for a group of undergraduate students studying business law units at Curtin University in Western…

  6. Mental workload in decision and control

    NASA Technical Reports Server (NTRS)

    Sheridan, T. B.

    1979-01-01

    This paper briefly reviews the problems of defining and measuring the 'mental workload' of aircraft pilots and other human operators of complex dynamic systems. Of the alternative approaches the author indicates a clear preference for the use of subjective scaling. Some recent experiments from MIT and elsewhere are described which utilize subjective mental workload scales in conjunction with human decision and control tasks in the laboratory. Finally a new three-dimensional mental workload rating scale, under current development for use by IFR aircraft pilots, is presented.

  7. Comparison between magnetic anchoring and guidance system camera-assisted laparoendoscopic single-site surgery nephrectomy and conventional laparoendoscopic single-site surgery nephrectomy in a porcine model: focus on ergonomics and workload profiles.

    PubMed

    Han, Woong Kyu; Tan, Yung K; Olweny, Ephrem O; Yin, Gang; Liu, Zhuo-Wei; Faddegon, Stephen; Scott, Daniel J; Cadeddu, Jeffrey A

    2013-04-01

    To compare surgeon-assessed ergonomic and workload demands of magnetic anchoring and guidance system (MAGS) laparoendoscopic single-site surgery (LESS) nephrectomy with conventional LESS nephrectomy in a porcine model. Participants included two expert and five novice surgeons who each performed bilateral LESS nephrectomy in two nonsurvival animals using either the MAGS camera or conventional laparoscope. Task difficulty and workload demands of the surgeon and camera driver were assessed using the validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire. Surgeons were also asked to score 6 parameters on a Likert scale (range 1=low/easy to 5=high/hard): procedure-associated workload, ergonomics, technical challenge, visualization, accidental events, and instrument handling. Each step of the nephrectomy was also timed and instrument clashing was quantified. Scores for each parameter on the Likert scale were significantly lower for MAGS-LESS nephrectomy. Mean number of internal and external clashes were significantly lower for the MAGS camera (p<0.001). Mean task times for each procedure were shorter for experts than for novices, but this was not statistically significant. NASA-TLX workload ratings by the surgeon and camera driver showed that MAGS resulted in a significantly lower workload than the conventional laparoscope during LESS nephrectomy (p<0.05). The use of the MAGS camera during LESS nephrectomy lowers the task workload for both the surgeon and camera driver when compared to conventional laparoscope use. Subjectively, it appears to also improve surgeons' impressions of ergonomics and technical challenge. Pending approval for clinical use, further evaluation in the clinical setting is warranted.

  8. The relationship between workload and training - An introduction

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G.

    1986-01-01

    This paper reviews the relationships among workload, performance, and training. Its goal is to introduce the concepts of workload and training and to suggest how they may be related. It suggests some of the practical and theoretical benefits to be derived from their joint consideration. Training effectiveness can be improved by monitoring trainee workload and the reliability of workload predictions, and measures can be improved by identifying and controlling the training levels of experimental subjects.

  9. Practical guidelines for workload assessment

    NASA Technical Reports Server (NTRS)

    Tattersall, Andrew J.

    1994-01-01

    The practical problems that might be encountered in carrying out workload evaluations in work settings have been outlined. Different approaches have been distinguished that may determine the type of research design used and provide assistance in the difficult choice between workload assessment techniques. One approach to workload assessment is to examine the short-term consequences of combining various tasks. Theoretical models of attention allocation will underpin specific studies of interference and the consequences of task demand and task conflict for performance. A further approach with a different temporal orientation may lead us to a better understanding of the relationships between work demands and strain through the analysis of individual differences in cognitive control processes. The application of these processes may depend on individual differences in long term styles and short term strategies, but may be used to prevent decrements in work performance under difficult conditions. However, control may attract costs as well as benefits in terms of changes in effective state and physiological activity. Thus, strain associated with work demands may only be measurable in the form of tradeoffs between performance and other domains of individual activity. The methodological implications are to identify patterns of adjustment to workload variations using repeated measures and longitudinal sampling of performance as well as subjective and physiological measures. Possible enhancements to workplace design must take into account these human factors considerations of workload in order to avoid potential decrements in individual performance and associated organizational problems.

  10. Personnel's Health Surveillance at Work: Effect of Age, Body Mass Index, and Shift Work on Mental Workload and Work Ability Index

    PubMed Central

    Safari, Shahram; Akbari, Jafar; Kazemi, Meghdad; Mououdi, Mohammad Amin; Mahaki, Behzad

    2013-01-01

    Introduction. Two great changes in developed countries are taking place: populations are ageing and becoming increasingly overweight. Combination of these factors with shift work is a risk factor for work ability and mental workload that are dynamic processes which change greatly throughout an individual's work life. The aim of this study was to investigate mental workload and work ability in textile workers and to identify factors which affect work ability and mental workload. Methods. This cross-sectional study was carried out among 194 male workers in textile industry. Employees based on their job group and work conditions have been divided into 6 categories. They completed work ability index and mental workload questionnaires during three work shifts. Body mass index (BMI) and demographic details were recorded. Results. All of the participants rated their work ability as moderate with high mental workload. The mean WAI and mental workload in age group were significant. The mean BMI was 25.5 kg/m2 (standard deviation 4.1) and the mean age was 40.22 years. There was a statistically significant correlation between work ability index and shift work. Conclusions. Unlike the previous study, a decrease point in WAI started in early age that may be due to life-style work and another psychological factor; on the other hand, NASA-TLX revealed high score in six subscales that can be another reason for low WAI. PMID:23956756

  11. Investigation of the charged particle nuclear reactions on natural boron for the purposes of the thin layer activation (TLA)

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Takács, S.; Tárkányi, F.; Fenyvesi, A.; Bergman, J.; Heselius, S.-J.; Solin, O.

    1995-12-01

    Boron of natural composition was investigated in the form of NiBSi metallic-glass foil to determine the cross-section functions of the natB(p,x) 7Be and the natB(d,x) 7Be nuclear reactions. These reactions are very important from the point of view of Thin Layer Activation (TLA) technique to monitor the wear of boron-containing superhard materials (e.g. BN), because the 7Be with its half-life of 53 d and gamma-energy of 447 keV is very suitable for wear measurements. The possibility of recoil-implantation of the radioactive nuclei was also studied.

  12. Downregulation of the CpSRP43 gene expression confers a truncated light-harvesting antenna (TLA) and enhances biomass and leaf-to-stem ratio in Nicotiana tabacum canopies.

    PubMed

    Kirst, Henning; Shen, Yanxin; Vamvaka, Evangelia; Betterle, Nico; Xu, Dongmei; Warek, Ujwala; Strickland, James A; Melis, Anastasios

    2018-04-06

    Downregulation in the expression of the signal recognition particle 43 (SRP43) gene in tobacco conferred a truncated photosynthetic light-harvesting antenna (TLA property), and resulted in plants with a greater leaf-to-stem ratio, improved photosynthetic productivity and canopy biomass accumulation under high-density cultivation conditions. Evolution of sizable arrays of light-harvesting antennae in all photosynthetic systems confers a survival advantage for the organism in the wild, where sunlight is often the growth-limiting factor. In crop monocultures, however, this property is strongly counterproductive, when growth takes place under direct and excess sunlight. The large arrays of light-harvesting antennae in crop plants cause the surface of the canopies to over-absorb solar irradiance, far in excess of what is needed to saturate photosynthesis and forcing them to engage in wasteful dissipation of the excess energy. Evidence in this work showed that downregulation by RNA-interference approaches of the Nicotiana tabacum signal recognition particle 43 (SRP43), a nuclear gene encoding a chloroplast-localized component of the photosynthetic light-harvesting assembly pathway, caused a decrease in the light-harvesting antenna size of the photosystems, a corresponding increase in the photosynthetic productivity of chlorophyll in the leaves, and improved tobacco plant canopy biomass accumulation under high-density cultivation conditions. Importantly, the resulting TLA transgenic plants had a substantially greater leaf-to-stem biomass ratio, compared to those of the wild type, grown under identical agronomic conditions. The results are discussed in terms of the potential benefit that could accrue to agriculture upon application of the TLA-technology to crop plants, entailing higher density planting with plants having a greater biomass and leaf-to-stem ratio, translating into greater crop yields per plant with canopies in a novel agronomic configuration.

  13. Managing Teacher Workload: Work-Life Balance and Wellbeing

    ERIC Educational Resources Information Center

    Bubb, Sara; Earley, Peter

    2004-01-01

    This book is divided into three sections. In the First Section, entitled "Wellbeing and Workload", the authors examine teacher workload and how teachers spend their time. Chapter 1 focuses on what the causes and effects of excessive workload are, especially in relation to wellbeing, stress and, crucially, recruitment and retention?…

  14. Quantitative EEG patterns of differential in-flight workload

    NASA Technical Reports Server (NTRS)

    Sterman, M. B.; Mann, C. A.; Kaiser, D. A.

    1993-01-01

    Four test pilots were instrumented for in-flight EEG recordings using a custom portable recording system. Each flew six, two minute tracking tasks in the Calspan NT-33 experimental trainer at Edwards AFB. With the canopy blacked out, pilots used a HUD display to chase a simulated aircraft through a random flight course. Three configurations of flight controls altered the flight characteristics to achieve low, moderate, and high workload, as determined by normative Cooper-Harper ratings. The test protocol was administered by a command pilot in the back seat. Corresponding EEG and tracking data were compared off-line. Tracking performance was measured as deviation from the target aircraft and combined with control difficulty to achieve an estimate of 'cognitive workload'. Trended patterns of parietal EEG activity at 8-12 Hz were sorted according to this classification. In all cases, high workload produced a significantly greater suppression of 8-12 Hz activity than low workload. Further, a clear differentiation of EEG trend patterns was obtained in 80 percent of the cases. High workload produced a sustained suppression of 8-12 Hz activity, while moderate workload resulted in an initial suppression followed by a gradual increment. Low workload was associated with a modulated pattern lacking any periods of marked or sustained suppression. These findings suggest that quantitative analysis of appropriate EEG measures may provide an objective and reliable in-flight index of cognitive effort that could facilitate workload assessment.

  15. Predicting workload profiles of brain-robot interface and electromygraphic neurofeedback with cortical resting-state networks: personal trait or task-specific challenge?

    NASA Astrophysics Data System (ADS)

    Fels, Meike; Bauer, Robert; Gharabaghi, Alireza

    2015-08-01

    Objective. Novel rehabilitation strategies apply robot-assisted exercises and neurofeedback tasks to facilitate intensive motor training. We aimed to disentangle task-specific and subject-related contributions to the perceived workload of these interventions and the related cortical activation patterns. Approach. We assessed the perceived workload with the NASA Task Load Index in twenty-one subjects who were exposed to two different feedback tasks in a cross-over design: (i) brain-robot interface (BRI) with haptic/proprioceptive feedback of sensorimotor oscillations related to motor imagery, and (ii) control of neuromuscular activity with feedback of the electromyography (EMG) of the same hand. We also used electroencephalography to examine the cortical activation patterns beforehand in resting state and during the training session of each task. Main results. The workload profile of BRI feedback differed from EMG feedback and was particularly characterized by the experience of frustration. The frustration level was highly correlated across tasks, suggesting subject-related relevance of this workload component. Those subjects who were specifically challenged by the respective tasks could be detected by an interhemispheric alpha-band network in resting state before the training and by their sensorimotor theta-band activation pattern during the exercise. Significance. Neurophysiological profiles in resting state and during the exercise may provide task-independent workload markers for monitoring and matching participants’ ability and task difficulty of neurofeedback interventions.

  16. A workload model and measures for computer performance evaluation

    NASA Technical Reports Server (NTRS)

    Kerner, H.; Kuemmerle, K.

    1972-01-01

    A generalized workload definition is presented which constructs measurable workloads of unit size from workload elements, called elementary processes. An elementary process makes almost exclusive use of one of the processors, CPU, I/O processor, etc., and is measured by the cost of its execution. Various kinds of user programs can be simulated by quantitative composition of elementary processes into a type. The character of the type is defined by the weights of its elementary processes and its structure by the amount and sequence of transitions between its elementary processes. A set of types is batched to a mix. Mixes of identical cost are considered as equivalent amounts of workload. These formalized descriptions of workloads allow investigators to compare the results of different studies quantitatively. Since workloads of different composition are assigned a unit of cost, these descriptions enable determination of cost effectiveness of different workloads on a machine. Subsequently performance parameters such as throughput rate, gain factor, internal and external delay factors are defined and used to demonstrate the effects of various workload attributes on the performance of a selected large scale computer system.

  17. Modified Petri net model sensitivity to workload manipulations

    NASA Technical Reports Server (NTRS)

    White, S. A.; Mackinnon, D. P.; Lyman, J.

    1986-01-01

    Modified Petri Nets (MPNs) are investigated as a workload modeling tool. The results of an exploratory study of the sensitivity of MPNs to work load manipulations in a dual task are described. Petri nets have been used to represent systems with asynchronous, concurrent and parallel activities (Peterson, 1981). These characteristics led some researchers to suggest the use of Petri nets in workload modeling where concurrent and parallel activities are common. Petri nets are represented by places and transitions. In the workload application, places represent operator activities and transitions represent events. MPNs have been used to formally represent task events and activities of a human operator in a man-machine system. Some descriptive applications demonstrate the usefulness of MPNs in the formal representation of systems. It is the general hypothesis herein that in addition to descriptive applications, MPNs may be useful for workload estimation and prediction. The results are reported of the first of a series of experiments designed to develop and test a MPN system of workload estimation and prediction. This first experiment is a screening test of MPN model general sensitivity to changes in workload. Positive results from this experiment will justify the more complicated analyses and techniques necessary for developing a workload prediction system.

  18. [Nursing workloads and working conditions: integrative review].

    PubMed

    Schmoeller, Roseli; Trindade, Letícia de Lima; Neis, Márcia Binder; Gelbcke, Francine Lima; de Pires, Denise Elvira Pires

    2011-06-01

    This study reviews theoretical production concerning workloads and working conditions for nurses. For that, an integrative review was carried out using scientific articles, theses and dissertations indexed in two Brazilian databases, Virtual Health Care Library (Biblioteca Virtual de Saúde) and Digital Database of Dissertations (Banco Digital de Teses), over the last ten years. From 132 identified studies, 27 were selected. Results indicate workloads as responsible for professional weariness, affecting the occurrence of work accidents and health problems. In order to adequate workloads studies indicate some strategies, such as having an adequate numbers of employees, continuing education, and better working conditions. The challenge is to continue research that reveal more precisely the relationships between workloads, working conditions, and health of the nursing team.

  19. Monitoring Workload in Throwing-Dominant Sports: A Systematic Review.

    PubMed

    Black, Georgia M; Gabbett, Tim J; Cole, Michael H; Naughton, Geraldine

    2016-10-01

    The ability to monitor training load accurately in professional sports is proving vital for athlete preparedness and injury prevention. While numerous monitoring techniques have been developed to assess the running demands of many team sports, these methods are not well suited to throwing-dominant sports that are infrequently linked to high running volumes. Therefore, other techniques are required to monitor the differing demands of these sports to ensure athletes are adequately prepared for competition. To investigate the different methodologies used to quantitatively monitor training load in throwing-dominant sports. A systematic review of the methods used to monitor training load in throwing-dominant sports was conducted using variations of terms that described different load-monitoring techniques and different sports. Studies included in this review were published prior to June 2015 and were identified through a systematic search of four electronic databases including Academic Search Complete, CINAHL, Medline and SPORTDiscus. Only full-length peer-reviewed articles investigating workload monitoring in throwing-dominant sports were selected for review. A total of 8098 studies were initially retrieved from the four databases and 7334 results were removed as they were either duplicates, review articles, non-peer-reviewed articles, conference abstracts or articles written in languages other than English. After screening the titles and abstracts of the remaining papers, 28 full-text papers were reviewed, resulting in the identification of 20 articles meeting the inclusion criteria for monitoring workloads in throwing-dominant sports. Reference lists of selected articles were then scanned to identify other potential articles, which yielded one additional article. Ten articles investigated workload monitoring in cricket, while baseball provided eight results, and handball, softball and water polo each contributed one article. Results demonstrated varying techniques

  20. File-access characteristics of parallel scientific workloads

    NASA Technical Reports Server (NTRS)

    Nieuwejaar, Nils; Kotz, David; Purakayastha, Apratim; Best, Michael; Ellis, Carla Schlatter

    1995-01-01

    Phenomenal improvements in the computational performance of multiprocessors have not been matched by comparable gains in I/O system performance. This imbalance has resulted in I/O becoming a significant bottleneck for many scientific applications. One key to overcoming this bottleneck is improving the performance of parallel file systems. The design of a high-performance parallel file system requires a comprehensive understanding of the expected workload. Unfortunately, until recently, no general workload studies of parallel file systems have been conducted. The goal of the CHARISMA project was to remedy this problem by characterizing the behavior of several production workloads, on different machines, at the level of individual reads and writes. The first set of results from the CHARISMA project describe the workloads observed on an Intel iPSC/860 and a Thinking Machines CM-5. This paper is intended to compare and contrast these two workloads for an understanding of their essential similarities and differences, isolating common trends and platform-dependent variances. Using this comparison, we are able to gain more insight into the general principles that should guide parallel file-system design.

  1. Subjective rating scales as a workload

    NASA Technical Reports Server (NTRS)

    Bird, K. L.

    1981-01-01

    A multidimensional bipolar-adjective rating scale is employed as a subjective measure of operator workload in the performance of a one-axis tracking task. The rating scale addressed several dimensions of workload, including cognitive, physical, and perceptual task loading as well as fatigue and stress effects. Eight subjects performed a one-axis tracking task (with six levels of difficulty) and rated these tasks on several workload dimensions. Performance measures were tracking error RMS (root-mean square) and the standard deviation of control stick output. Significant relationships were observed between these performance measures and skill required, task complexity, attention level, task difficulty, task demands, and stress level.

  2. [Do physicians' gender and workload affect patients?].

    PubMed

    Finnvold, Jon Erik

    2008-10-23

    The article discusses the effect of general practitioners' gender and workload on patients' experience with consultation time, waiting hours, use of out-of-hours services and planned health visits. Data were retrieved from the 2003 version of Statistics Norway's household panel study (5000 persons) and the National Insurance administration's register of regular general practitioners. Health condition was the most important factor related to patient experiences. A high workload was neither associated with more frequent use of out-of-hours services nor satisfaction with time spent in consultation. These results apply to physicians of both genders. Patients who used a female physician with a large workload had to wait longer for an appointment and more often reported dissatisfaction with the waiting time; this was not the case for male physicians. However, male physicians with a low workload had shorter waiting times. Patients who use practitioners with a high workload may have chosen their doctor more deliberately than others, which may be an explanation for few negative outcomes for physicians with a high workload. It is unlikely that these physicians would be as popular if the patients had fewer appointments, shorter consultations or more often had to use the out-of-hours services. Longer waiting time for appointments with female doctors may be related to more part time work, and the fact that female physicians more often are engaged in group practices.

  3. Physiological correlates of mental workload

    NASA Technical Reports Server (NTRS)

    Zacharias, G. L.

    1980-01-01

    A literature review was conducted to assess the basis of and techniques for physiological assessment of mental workload. The study findings reviewed had shortcomings involving one or more of the following basic problems: (1) physiologic arousal can be easily driven by nonworkload factors, confounding any proposed metric; (2) the profound absence of underlying physiologic models has promulgated a multiplicity of seemingly arbitrary signal processing techniques; (3) the unspecified multidimensional nature of physiological "state" has given rise to a broad spectrum of competing noncommensurate metrics; and (4) the lack of an adequate definition of workload compels physiologic correlations to suffer either from the vagueness of implicit workload measures or from the variance of explicit subjective assessments. Using specific studies as examples, two basic signal processing/data reduction techniques in current use, time and ensemble averaging are discussed.

  4. Strategic workload management and decision biases in aviation

    NASA Technical Reports Server (NTRS)

    Raby, Mireille; Wickens, Christopher D.

    1994-01-01

    Thirty pilots flew three simulated landing approaches under conditions of low, medium, and high workload. Workload conditions were created by varying time pressure and external communications requirements. Our interest was in how the pilots strategically managed or adapted to the increasing workload. We independently assessed the pilot's ranking of the priority of different discrete tasks during the approach and landing. Pilots were found to sacrifice some aspects of primary flight control as workload increased. For discrete tasks, increasing workload increased the amount of time in performing the high priority tasks, decreased the time in performing those of lowest priority, and did not affect duration of performance episodes or optimality of scheduling of tasks of any priority level. Individual differences analysis revealed that high-performing subjects scheduled discrete tasks earlier in the flight and shifted more often between different activities.

  5. Pilot workload, performance and aircraft control automation

    NASA Technical Reports Server (NTRS)

    Hart, S. G.; Sheridan, T. B.

    1984-01-01

    Conceptual and practical issues associated with the design, operation, and performance of advanced systems and the impact of such systems on the human operators are reviewed. The development of highly automated systems is driven by the availability of new technology and the requirement that operators safely and economically perform more and more activities in increasingly difficult and hostile environments. It is noted that the operators workload may become a major area of concern in future design considerations. Little research was done to determine how automation and workload relate to each other, although it is assumed that the abstract, supervisory, or management roles that are performed by operators of highly automated systems will impose increased mental workload. The relationship between performance and workload is discussed in relation to highly complex and automated environments.

  6. Timesharing performance as an indicator of pilot mental workload

    NASA Technical Reports Server (NTRS)

    Casper, Patricia A.; Kantowitz, Barry H.; Sorkin, Robert D.

    1988-01-01

    Attentional deficits (workloads) were evaluated in a timesharing task. The results from this and other experiments were incorporated into an expert system designed to provide workload metric selection advice to non-experts in the field interested in operator workload.

  7. Smartphone form factors: Effects of width and bottom bezel on touch performance, workload, and physical demand.

    PubMed

    Lee, Seul Chan; Cha, Min Chul; Hwangbo, Hwan; Mo, Sookhee; Ji, Yong Gu

    2018-02-01

    This study aimed at investigating the effect of two smartphone form factors (width and bottom bezel) on touch behaviors with one-handed interaction. User experiments on tapping tasks were conducted for four widths (67, 70, 72, and 74 mm) and five bottom bezel levels (2.5, 5, 7.5, 10, and 12.5 mm). Task performance, electromyography, and subjective workload data were collected to examine the touch behavior. The success rate and task completion time were collected as task performance measures. The NASA-TLX method was used to observe the subjective workload. The electromyogram signals of two thumb muscles, namely the first dorsal interosseous and abductor pollicis brevis, were observed. The task performances deteriorated with increasing width level. The subjective workload and electromyography data showed similar patterns with the task performances. The task performances of the bottom bezel devices were analyzed by using three different evaluation criteria. The results from these criteria indicated that tasks became increasingly difficult as the bottom bezel level decreased. The results of this study provide insights into the optimal range of smartphone form factors for one-handed interaction, which could contribute to the design of new smartphones. Copyright © 2017. Published by Elsevier Ltd.

  8. Timesharing performance as an indicator of pilot mental workload

    NASA Technical Reports Server (NTRS)

    Casper, Patricia A.

    1988-01-01

    The research was performed in two simultaneous phases, each intended to identify and manipulate factors related to operator mental workload. The first phase concerned evaluation of attentional deficits (workloads) in a timesharing task. Work in the second phase involved incorporating the results from these and other experiments into an expert system designed to provide workload metric selection advice to nonexperts in the field interested in operator workload. The results of the experiments conducted are summarized.

  9. Measuring Pilot Workload in a Moving-base Simulator. Part 2: Building Levels of Workload

    NASA Technical Reports Server (NTRS)

    Kantowitz, B. H.; Hart, S. G.; Bortolussi, M. R.; Shively, R. J.; Kantowitz, S. C.

    1984-01-01

    Pilot behavior in flight simulators often use a secondary task as an index of workload. His routine to regard flying as the primary task and some less complex task as the secondary task. While this assumption is quite reasonable for most secondary tasks used to study mental workload in aircraft, the treatment of flying a simulator through some carefully crafted flight scenario as a unitary task is less justified. The present research acknowledges that total mental workload depends upon the specific nature of the sub-tasks that a pilot must complete as a first approximation, flight tasks were divided into three levels of complexity. The simplest level (called the Base Level) requires elementary maneuvers that do not utilize all the degrees of freedom of which an aircraft, or a moving-base simulator; is capable. The second level (called the Paired Level) requires the pilot to simultaneously execute two Base Level tasks. The third level (called the Complex Level) imposes three simultaneous constraints upon the pilot.

  10. Factors Related to School Nurse Workload

    ERIC Educational Resources Information Center

    Jameson, Beth E.; Engelke, Martha Keehner; Anderson, Lori S.; Endsley, Patricia; Maughan, Erin D.

    2018-01-01

    Recognizing the need for a school nurse workload model based on more than the number of students in a caseload, the National Association of School Nurses issued recommendations related to measuring school nurse workload. Next, a workforce acuity task force (WATF) was charged with identifying the steps needed to further the recommendations. As a…

  11. School Nurse Workload: A Scoping Review of Acute Care, Community Health, and Mental Health Nursing Workload Literature

    ERIC Educational Resources Information Center

    Endsley, Patricia

    2017-01-01

    The purpose of this scoping review was to survey the most recent (5 years) acute care, community health, and mental health nursing workload literature to understand themes and research avenues that may be applicable to school nursing workload research. The search for empirical and nonempirical literature was conducted using search engines such as…

  12. Exploring Individual Differences in Workload Assessment

    DTIC Science & Technology

    2014-12-26

    83 Question 3: Do the physiological measures: blinks, saccades, HR, HRV , correlate with the objective workload profile for all...Electrooculography (EOG) signals, and heart rate (HR) and heart rate variability ( HRV ) as determined from Electrocardiography (ECG...3) Do the physiological measures blinks, saccades, HR, and HRV , correlate with the objective workload profile for all divergent participants and

  13. An Annotated Bibliography on Operator Mental Workload Assessment

    DTIC Science & Technology

    1980-03-26

    The descriptors associated with each citation designate the general workload classification, the specific workload classification, tue type of...systems, with all of their advanced sen3ors and avionics, must be compatible with the capabilities and limitations of the aircrew. During the design ...constructs or models was included only if mental workload was at least potentially assessable from the constructs or models. C. Experimental design . A

  14. Workload Measurement in Human Autonomy Teaming: How and Why?

    NASA Technical Reports Server (NTRS)

    Shively, Jay

    2016-01-01

    This is an invited talk on autonomy and workload for an AFRL Blue Sky workshop sponsored by the Florida Institute for Human Machine Studies. The presentation reviews various metrics of workload and how to move forward with measuring workload in a human-autonomy teaming environment.

  15. Analysis of mental workload of electrical power plant operators of control and operation centers.

    PubMed

    Vitório, Daiana Martins; Masculo, Francisco Soares; Melo, Miguel O B C

    2012-01-01

    Electrical systems can be categorized as critical systems where failure can result in significant financial loss, injury or threats to human life. The operators of the electric power control centers perform an activity in a specialized environment and have to carry it out by mobilizing knowledge and reasoning to which they have adequate training under the terms of the existing rules. To reach this there is a common mental request of personnel involved in these centers due the need to maintain attention, memory and reasoning request. In this sense, this study aims to evaluate the Mental Workload of technical workers of the Control Centers of Electrical Energy. It was undertaken a research on operators control centers of the electricity sector in Northeast Brazil. It was used for systematic observations, followed by interview and application of the instrument National Aeronautics and Space Administration Task Load Index known as NASA-TLX. As a result there will be subsidies for an assessment of mental workload of operators, and a contribution to improving the processes of managing the operation of electric utilities and the quality of workers.

  16. How Do Clinical Information Systems Affect the Cognitive Demands of General Practitioners?: Usability Study with a Focus on Cognitive Workload.

    PubMed

    Ariza, Ferran; Kalra, Dipak; Potts, Henry Ww

    2015-11-20

    Clinical information systems in the National Health Service do not need to conform to any explicit usability requirements. Poor usability can increase the mental workload experienced by clinicians and cause fatigue, increase error rates and impact the overall patient safety. Mental workload can be used as a measure of usability. To assess the subjective cognitive workload experienced by general practitioners (GPs) with their systems. To raise awareness of the importance of usability in system design among users, designers, developers and policymakers. We used a modified version of the NASA Task Load Index, adapted for web. We developed a set of common clinical scenarios and computer tasks on an online survey. We emailed the study link to 199 clinical commissioning groups and 1,646 GP practices in England. Sixty-seven responders completed the survey. The respondents had spent an average of 17 years in general practice, had experience of using a mean of 1.5 GP computer systems and had used their current system for a mean time of 6.7 years. The mental workload score was not different among systems. There were significant differences among the task scores, but these differences were not specific to particular systems. The overall score and task scores were related to the length of experience with their present system. Four tasks imposed a higher mental workload on GPs: 'repeat prescribing', 'find episode', 'drug management' and 'overview records'. Further usability studies on GP systems should focus on these tasks. Users, policymakers, designers and developers should remain aware of the importance of usability in system design.What does this study add?• Current GP systems in England do not need to conform to explicit usability requirements. Poor usability can increase the mental workload of clinicians and lead to errors.• Some clinical computer tasks incur more cognitive workload than others and should be considered carefully during the design of a system.• GPs

  17. Front-line ordering clinicians: matching workforce to workload.

    PubMed

    Fieldston, Evan S; Zaoutis, Lisa B; Hicks, Patricia J; Kolb, Susan; Sladek, Erin; Geiger, Debra; Agosto, Paula M; Boswinkel, Jan P; Bell, Louis M

    2014-07-01

    Matching workforce to workload is particularly important in healthcare delivery, where an excess of workload for the available workforce may negatively impact processes and outcomes of patient care and resident learning. Hospitals currently lack a means to measure and match dynamic workload and workforce factors. This article describes our work to develop and obtain consensus for use of an objective tool to dynamically match the front-line ordering clinician (FLOC) workforce to clinical workload in a variety of inpatient settings. We undertook development of a tool to represent hospital workload and workforce based on literature reviews, discussions with clinical leadership, and repeated validation sessions. We met with physicians and nurses from every clinical care area of our large, urban children's hospital at least twice. We successfully created a tool in a matrix format that is objective and flexible and can be applied to a variety of settings. We presented the tool in 14 hospital divisions and received widespread acceptance among physician, nursing, and administrative leadership. The hospital uses the tool to identify gaps in FLOC coverage and guide staffing decisions. Hospitals can better match workload to workforce if they can define and measure these elements. The Care Model Matrix is a flexible, objective tool that quantifies the multidimensional aspects of workload and workforce. The tool, which uses multiple variables that are easily modifiable, can be adapted to a variety of settings. © 2014 Society of Hospital Medicine.

  18. A comparison of policies on nurse faculty workload in the United States.

    PubMed

    Ellis, Peggy A

    2013-01-01

    This article describes nurse faculty workload policies from across the nation in order to assess current practice. There is a well-documented shortage of nursing faculty leading to an increase in workload demands. Increases in faculty workload results in difficulties with work-life balance and dissatisfaction threatening to make nursing education less attractive to young faculty. In order to begin an examination of faculty workload in nursing, existing workloads must be known. Faculty workload data were solicited from nursing programs nationwide and analyzed to determine the current workloads. The most common faculty teaching workload reported overall for nursing is 12 credit hours per semester; however, some variations exist. Consideration should be given to the multiple components of the faculty workload. Research is needed to address the most effective and efficient workload allocation for nursing faculty.

  19. Making the transition to workload-based staffing: using the Workload Indicators of Staffing Need method in Uganda.

    PubMed

    Namaganda, Grace; Oketcho, Vincent; Maniple, Everd; Viadro, Claire

    2015-08-31

    Uganda's health workforce is characterized by shortages and inequitable distribution of qualified health workers. To ascertain staffing levels, Uganda uses fixed government-approved norms determined by facility type. This approach cannot distinguish between facilities of the same type that have different staffing needs. The Workload Indicators of Staffing Need (WISN) method uses workload to determine number and type of staff required in a given facility. The national WISN assessment sought to demonstrate the limitations of the existing norms and generate evidence to influence health unit staffing and staff deployment for efficient utilization of available scarce human resources. A national WISN assessment (September 2012) used purposive sampling to select 136 public health facilities in 33/112 districts. The study examined staffing requirements for five cadres (nursing assistants, nurses, midwives, clinical officers, doctors) at health centres II (n = 59), III (n = 53) and IV (n = 13) and hospitals (n = 11). Using health management information system workload data (1 July 2010-30 June 2011), the study compared current and required staff, assessed workload pressure and evaluated the adequacy of the existing staffing norms. By the WISN method, all three types of health centres had fewer nurses (42-70%) and midwives (53-67%) than required and consequently exhibited high workload pressure (30-58%) for those cadres. Health centres IV and hospitals lacked doctors (39-42%) but were adequately staffed with clinical officers. All facilities displayed overstaffing of nursing assistants. For all cadres at health centres III and IV other than nursing assistants, the fixed norms or existing staffing or both fell short of the WISN staffing requirements, with, for example, only half as many nurses and midwives as required. The WISN results demonstrate the inadequacies of existing staffing norms, particularly for health centres III and IV. The results provide an evidence base to

  20. The Effects of Aviation Weather Information Systems on General Aviation Weather Information Systems on General Pilots' Workload

    NASA Technical Reports Server (NTRS)

    Scerbo, Mark; Coyne, Joseph; Burt, Jennifer L. (Technical Monitor)

    2002-01-01

    My work at NASA Langley has focused around Aviation Weather Information CAWING displays. The majority of my time at LYRIC has been spent on the Workload and Relative Position (WaRP) Study. The goal of this project is to determine how an AWIN display at various positions within the cockpit affects pilot performance and workload. The project is being conducted in Languages Cessna 206H research aircraft. During the past year the design of the experiment was finalized and approved. Despite facing several delays the data collection was completed in early February. Alter the completion of the data collection an extensive data entry task began. This required recording air speed, altitude, course heading, bank angle, and vertical speed information from videos of the primary flight displays. This data was then used to determine root mean square error (RMSE) for each experimental condition. In addition to the performance data (RMSE) taken from flight path deviation, the study also collected data on pilot;s accuracy in reporting weather information, and a subjective rating of workload from the pilot. The data for this experiment is currently being analyzed. Overall the current experiment should help to determine potential costs and benefits associated with AWIN displays. The data will be used to determine if a private pilot can safely fly a general aviation aircraft while operating a weather display. Clearly a display that adds to the pilot#s already heavy workload represents a potential problem. The study will compare the use of an AWIN display to conventional means of acquiring weather data. The placement of the display within the cockpit (i.e., either on the yoke, kneeboard, or panel) will be also compared in terms of workload, performance, and pilot preference.

  1. Assessing Continuous Operator Workload With a Hybrid Scaffolded Neuroergonomic Modeling Approach.

    PubMed

    Borghetti, Brett J; Giametta, Joseph J; Rusnock, Christina F

    2017-02-01

    We aimed to predict operator workload from neurological data using statistical learning methods to fit neurological-to-state-assessment models. Adaptive systems require real-time mental workload assessment to perform dynamic task allocations or operator augmentation as workload issues arise. Neuroergonomic measures have great potential for informing adaptive systems, and we combine these measures with models of task demand as well as information about critical events and performance to clarify the inherent ambiguity of interpretation. We use machine learning algorithms on electroencephalogram (EEG) input to infer operator workload based upon Improved Performance Research Integration Tool workload model estimates. Cross-participant models predict workload of other participants, statistically distinguishing between 62% of the workload changes. Machine learning models trained from Monte Carlo resampled workload profiles can be used in place of deterministic workload profiles for cross-participant modeling without incurring a significant decrease in machine learning model performance, suggesting that stochastic models can be used when limited training data are available. We employed a novel temporary scaffold of simulation-generated workload profile truth data during the model-fitting process. A continuous workload profile serves as the target to train our statistical machine learning models. Once trained, the workload profile scaffolding is removed and the trained model is used directly on neurophysiological data in future operator state assessments. These modeling techniques demonstrate how to use neuroergonomic methods to develop operator state assessments, which can be employed in adaptive systems.

  2. Comparative evaluation of workload estimation techniques in piloting tasks

    NASA Technical Reports Server (NTRS)

    Wierwille, W. W.

    1983-01-01

    Techniques to measure operator workload in a wide range of situations and tasks were examined. The sensitivity and intrusion of a wide variety of workload assessment techniques in simulated piloting tasks were investigated. Four different piloting tasks, psychomotor, perceptual, mediational, and communication aspects of piloting behavior were selected. Techniques to determine relative sensitivity and intrusion were applied. Sensitivity is the relative ability of a workload estimation technique to discriminate statistically significant differences in operator loading. High sensitivity requires discriminable changes in score means as a function of load level and low variation of the scores about the means. Intrusion is an undesirable change in the task for which workload is measured, resulting from the introduction of the workload estimation technique or apparatus.

  3. Assessing Clinical Trial-Associated Workload in Community-Based Research Programs Using the ASCO Clinical Trial Workload Assessment Tool.

    PubMed

    Good, Marjorie J; Hurley, Patricia; Woo, Kaitlin M; Szczepanek, Connie; Stewart, Teresa; Robert, Nicholas; Lyss, Alan; Gönen, Mithat; Lilenbaum, Rogerio

    2016-05-01

    Clinical research program managers are regularly faced with the quandary of determining how much of a workload research staff members can manage while they balance clinical practice and still achieve clinical trial accrual goals, maintain data quality and protocol compliance, and stay within budget. A tool was developed to measure clinical trial-associated workload, to apply objective metrics toward documentation of work, and to provide clearer insight to better meet clinical research program challenges and aid in balancing staff workloads. A project was conducted to assess the feasibility and utility of using this tool in diverse research settings. Community-based research programs were recruited to collect and enter clinical trial-associated monthly workload data into a web-based tool for 6 consecutive months. Descriptive statistics were computed for self-reported program characteristics and workload data, including staff acuity scores and number of patient encounters. Fifty-one research programs that represented 30 states participated. Median staff acuity scores were highest for staff with patients enrolled in studies and receiving treatment, relative to staff with patients in follow-up status. Treatment trials typically resulted in higher median staff acuity, relative to cancer control, observational/registry, and prevention trials. Industry trials exhibited higher median staff acuity scores than trials sponsored by the National Institutes of Health/National Cancer Institute, academic institutions, or others. The results from this project demonstrate that trial-specific acuity measurement is a better measure of workload than simply counting the number of patients. The tool was shown to be feasible and useable in diverse community-based research settings. Copyright © 2016 by American Society of Clinical Oncology.

  4. Assessing Clinical Trial–Associated Workload in Community-Based Research Programs Using the ASCO Clinical Trial Workload Assessment Tool

    PubMed Central

    Hurley, Patricia; Woo, Kaitlin M.; Szczepanek, Connie; Stewart, Teresa; Robert, Nicholas; Lyss, Alan; Gönen, Mithat; Lilenbaum, Rogerio

    2016-01-01

    Purpose: Clinical research program managers are regularly faced with the quandary of determining how much of a workload research staff members can manage while they balance clinical practice and still achieve clinical trial accrual goals, maintain data quality and protocol compliance, and stay within budget. A tool was developed to measure clinical trial–associated workload, to apply objective metrics toward documentation of work, and to provide clearer insight to better meet clinical research program challenges and aid in balancing staff workloads. A project was conducted to assess the feasibility and utility of using this tool in diverse research settings. Methods: Community-based research programs were recruited to collect and enter clinical trial–associated monthly workload data into a web-based tool for 6 consecutive months. Descriptive statistics were computed for self-reported program characteristics and workload data, including staff acuity scores and number of patient encounters. Results: Fifty-one research programs that represented 30 states participated. Median staff acuity scores were highest for staff with patients enrolled in studies and receiving treatment, relative to staff with patients in follow-up status. Treatment trials typically resulted in higher median staff acuity, relative to cancer control, observational/registry, and prevention trials. Industry trials exhibited higher median staff acuity scores than trials sponsored by the National Institutes of Health/National Cancer Institute, academic institutions, or others. Conclusion: The results from this project demonstrate that trial-specific acuity measurement is a better measure of workload than simply counting the number of patients. The tool was shown to be feasible and useable in diverse community-based research settings. PMID:27006354

  5. Prediction of Nursing Workload in Hospital.

    PubMed

    Fiebig, Madlen; Hunstein, Dirk; Bartholomeyczik, Sabine

    2018-01-01

    A dissertation project at the Witten/Herdecke University [1] is investigating which (nursing sensitive) patient characteristics are suitable for predicting a higher or lower degree of nursing workload. For this research project four predictive modelling methods were selected. In a first step, SUPPORT VECTOR MACHINE, RANDOM FOREST, and GRADIENT BOOSTING were used to identify potential predictors from the nursing sensitive patient characteristics. The results were compared via FEATURE IMPORTANCE. To predict nursing workload the predictors identified in step 1 were modelled using MULTINOMIAL LOGISTIC REGRESSION. First results from the data mining process will be presented. A prognostic determination of nursing workload can be used not only as a basis for human resource planning in hospital, but also to respond to health policy issues.

  6. Performance Analysis of the NAS Y-MP Workload

    NASA Technical Reports Server (NTRS)

    Bergeron, Robert J.; Kutler, Paul (Technical Monitor)

    1997-01-01

    This paper describes the performance characteristics of the computational workloads on the NAS Cray Y-MP machines, a Y-MP 832 and later a Y-MP 8128. Hardware measurements indicated that the Y-MP workload performance matured over time, ultimately sustaining an average throughput of 0.8 GFLOPS and a vector operation fraction of 87%. The measurements also revealed an operation rate exceeding 1 per clock period, a well-balanced architecture featuring a strong utilization of vector functional units, and an efficient memory organization. Introduction of the larger memory 8128 increased throughput by allowing a more efficient utilization of CPUs. Throughput also depended on the metering of the batch queues; low-idle Saturday workloads required a buffer of small jobs to prevent memory starvation of the CPU. UNICOS required about 7% of total CPU time to service the 832 workloads; this overhead decreased to 5% for the 8128 workloads. While most of the system time went to service I/O requests, efficient scheduling prevented excessive idle due to I/O wait. System measurements disclosed no obvious bottlenecks in the response of the machine and UNICOS to the workloads. In most cases, Cray-provided software tools were- quite sufficient for measuring the performance of both the machine and operating, system.

  7. Assessing physician job satisfaction and mental workload.

    PubMed

    Boultinghouse, Oscar W; Hammack, Glenn G; Vo, Alexander H; Dittmar, Mary Lynne

    2007-12-01

    Physician job satisfaction and mental workload were evaluated in a pilot study of five physicians engaged in a telemedicine practice at The University of Texas Medical Branch at Galveston Electronic Health Network. Several previous studies have examined physician satisfaction with specific telemedicine applications; however, few have attempted to identify the underlying factors that contribute to physician satisfaction or lack thereof. One factor that has been found to affect well-being and functionality in the workplace-particularly with regard to human interaction with complex systems and tasks as seen in telemedicine-is mental workload. Workload is generally defined as the "cost" to a person for performing a complex task or tasks; however, prior to this study, it was unexplored as a variable that influences physician satisfaction. Two measures of job satisfaction were used: The Job Descriptive Index and the Job In General scales. Mental workload was evaluated by means of the National Aeronautics and Space Administration Task Load Index. The measures were administered by means of Web-based surveys and were given twice over a 6-month period. Nonparametric statistical analyses revealed that physician job satisfaction was generally high relative to that of the general population and other professionals. Mental workload scores associated with the practice of telemedicine in this environment are also high, and appeared stable over time. In addition, they are commensurate with scores found in individuals practicing tasks with elevated information-processing demands, such as quality control engineers and air traffic controllers. No relationship was found between the measures of job satisfaction and mental workload.

  8. The Impact of Data Communications Messages in the Terminal Area on Flight Crew Workload and Eye Scanning

    NASA Technical Reports Server (NTRS)

    Comstock, James R., Jr.; Baxley, Brian T.; Norman, Robert M.; Ellis, Kyle K. E.; Adams, Cathy A.; Latorella, Kara A.; Lynn, William A.

    2010-01-01

    This paper, to accompany a discussion panel, describes a collaborative FAA and NASA research study to determine the effect Data Communications (Data Comm) messages have on flight crew workload and eye scanning behavior in busy terminal area operations. In the Next Generation Air Transportation System Concept of Operations, for the period 2017-2022, the FAA envisions Data Comm between controllers and the flight crew to become the primary means of communicating non-time critical information. Four research conditions were defined that span current day to future equipage levels (Voice with Paper map, Data Comm with Paper map, Data Comm with Moving Map Display with ownship position displayed, Data Comm with Moving Map, ownship and taxi route displayed), and were used to create arrival and departure scenarios at Boston Logan Airport. Preliminary results for workload, situation awareness, and pilot head-up time are presented here. Questionnaire data indicated that pilot acceptability, workload, and situation awareness ratings were favorable for all of the conditions tested. Pilots did indicate that there were times during final approach and landing when they would prefer not to hear the message chime, and would not be able to make a quick response due to high priority tasks in the cockpit.

  9. The Impact of Operating Room Distractions on Stress, Workload, and Teamwork.

    PubMed

    Wheelock, Ana; Suliman, Amna; Wharton, Rupert; Babu, E D; Hull, Louise; Vincent, Charles; Sevdalis, Nick; Arora, Sonal

    2015-06-01

    To investigate whether distractions in the operating room (OR) are associated with higher mental workload and stress, and poorer teamwork among OR personnel. Engaging in multiple tasks can affect performance. There is little research on the effect of distractions on surgical team members' behavior and cognitive processes. Ninety general surgery cases were observed in real time. Cases were assessed by a surgeon and a behavioral scientist using 4 validated tools: OR Distractions Assessment Form, the Observational Teamwork Assessment for Surgery tool, NASA-Task Load Index, and short form of the State Trait Anxiety Inventory. Analysis of variance was performed to evaluate significant differences between teamwork, workload, and stress level among team members. Correlations (Pearson r) were computed to evaluate associations between variables. The most prevalent distractions were those initiated by external staff, followed by case-irrelevant conversations. Case-irrelevant conversations were associated with poorer team performance. Irrelevant conversations initiated by surgeons were associated with lower teamwork in surgeons (across team skills: r = -0.44 to -0.58, P < 0.05 to 0.01) and anesthesiologists (r = -0.38 and r = -0.40, for coordination and leadership; P < 0.05). Equipment-related distractions correlated with higher stress (r = 0.48, P < 0.05) and lower teamwork (across team skills: r = -0.42 to -0.50, P < 0.05) in nurses. Acoustic distractions correlated with higher stress in surgeons (r = 0.32, P < 0.05) and higher workload in anesthesiologists (r = 0.30, P < 0.05). Although some distractions may be inevitable in the OR, they can also be detrimental to the team. A deeper understanding of the effect of distractions on teams and their outcomes can lead to targeted quality improvement.

  10. Activity-based differentiation of pathologists' workload in surgical pathology.

    PubMed

    Meijer, G A; Oudejans, J J; Koevoets, J J M; Meijer, C J L M

    2009-06-01

    Adequate budget control in pathology practice requires accurate allocation of resources. Any changes in types and numbers of specimens handled or protocols used will directly affect the pathologists' workload and consequently the allocation of resources. The aim of the present study was to develop a model for measuring the pathologists' workload that can take into account the changes mentioned above. The diagnostic process was analyzed and broken up into separate activities. The time needed to perform these activities was measured. Based on linear regression analysis, for each activity, the time needed was calculated as a function of the number of slides or blocks involved. The total pathologists' time required for a range of specimens was calculated based on standard protocols and validated by comparing to actually measured workload. Cutting up, microscopic procedures and dictating turned out to be highly correlated to number of blocks and/or slides per specimen. Calculated workload per type of specimen was significantly correlated to the actually measured workload. Modeling pathologists' workload based on formulas that calculate workload per type of specimen as a function of the number of blocks and slides provides a basis for a comprehensive, yet flexible, activity-based costing system for pathology.

  11. Workload Characterization of CFD Applications Using Partial Differential Equation Solvers

    NASA Technical Reports Server (NTRS)

    Waheed, Abdul; Yan, Jerry; Saini, Subhash (Technical Monitor)

    1998-01-01

    Workload characterization is used for modeling and evaluating of computing systems at different levels of detail. We present workload characterization for a class of Computational Fluid Dynamics (CFD) applications that solve Partial Differential Equations (PDEs). This workload characterization focuses on three high performance computing platforms: SGI Origin2000, EBM SP-2, a cluster of Intel Pentium Pro bases PCs. We execute extensive measurement-based experiments on these platforms to gather statistics of system resource usage, which results in workload characterization. Our workload characterization approach yields a coarse-grain resource utilization behavior that is being applied for performance modeling and evaluation of distributed high performance metacomputing systems. In addition, this study enhances our understanding of interactions between PDE solver workloads and high performance computing platforms and is useful for tuning these applications.

  12. Effects of workload preview on task scheduling during simulated instrument flight.

    PubMed

    Andre, A D; Heers, S T; Cashion, P A

    1995-01-01

    Our study examined pilot scheduling behavior in the context of simulated instrument flight. Over the course of the flight, pilots flew along specified routes while scheduling and performing several flight-related secondary tasks. The first phase of flight was flown under low-workload conditions, whereas the second phase of flight was flown under high-workload conditions in the form of increased turbulence and a disorganized instrument layout. Six pilots were randomly assigned to each of three workload preview groups. Subjects in the no-preview group were not given preview of the increased-workload conditions. Subjects in the declarative preview group were verbally informed of the nature of the flight workload manipulation but did not receive any practice under the high-workload conditions. Subjects in the procedural preview group received the same instructions as the declarative preview group but also flew half of the practice flight under the high-workload conditions. The results show that workload preview fostered efficient scheduling strategies. Specifically, those pilots with either declarative or procedural preview of future workload demands adopted an efficient strategy of scheduling more of the difficult secondary tasks during the low-workload phase of flight. However, those pilots given a procedural preview showed the greatest benefits in overall flight performance.

  13. An attempt to estimate students' workload.

    PubMed

    Pogacnik, M; Juznic, P; Kosorok-Drobnic, M; Pogacnik, A; Cestnik, V; Kogovsek, J; Pestevsek, U; Fernandes, Tito

    2004-01-01

    Following the recent introduction of the European Credit Transfer System (ECTS) into several European university programs, a new interest has developed in determining students' workload. ECTS credits are numerical values describing the student workload required to complete course units; ECTS has the potential to facilitate comparison and create transparency between institutional curricula. ECTS credits are frequently listed alongside institutional credits in course outlines and module summaries. Measuring student workload has been difficult; to a large extent, estimates are based only upon anecdotal and casual information. To gather more systematic information, we asked students at the Veterinary Faculty, University of Ljubljana, to estimate the actual total workload they committed to fulfill their coursework obligations for specific subjects in the veterinary degree program by reporting their attendance at defined contact hours and their estimated time for outside study, including the time required for examinations and other activities. Students also reported the final grades they received for these subjects. The results show that certain courses require much more work than others, independent of credit unit assignment. Generally, the courses with more contact hours tend also to demand more independent work; the best predictor of both actual student workload and student success is the amount of contact time in which they participate. The data failed to show any strong connection between students' total workload and grades they received; rather, they showed some evidence that regular presence at contact hours was the most positive influence on grades. Less frequent presence at lectures tended to indicate less time spent on independent study. It was also found that pre-clinical and clinical courses tended to require more work from students than other, more general subjects. While the present study does not provide conclusive evidence, it does indicate the need for

  14. State of science: mental workload in ergonomics.

    PubMed

    Young, Mark S; Brookhuis, Karel A; Wickens, Christopher D; Hancock, Peter A

    2015-01-01

    Mental workload (MWL) is one of the most widely used concepts in ergonomics and human factors and represents a topic of increasing importance. Since modern technology in many working environments imposes ever more cognitive demands upon operators while physical demands diminish, understanding how MWL impinges on performance is increasingly critical. Yet, MWL is also one of the most nebulous concepts, with numerous definitions and dimensions associated with it. Moreover, MWL research has had a tendency to focus on complex, often safety-critical systems (e.g. transport, process control). Here we provide a general overview of the current state of affairs regarding the understanding, measurement and application of MWL in the design of complex systems over the last three decades. We conclude by discussing contemporary challenges for applied research, such as the interaction between cognitive workload and physical workload, and the quantification of workload 'redlines' which specify when operators are approaching or exceeding their performance tolerances.

  15. Online EEG-Based Workload Adaptation of an Arithmetic Learning Environment.

    PubMed

    Walter, Carina; Rosenstiel, Wolfgang; Bogdan, Martin; Gerjets, Peter; Spüler, Martin

    2017-01-01

    In this paper, we demonstrate a closed-loop EEG-based learning environment, that adapts instructional learning material online, to improve learning success in students during arithmetic learning. The amount of cognitive workload during learning is crucial for successful learning and should be held in the optimal range for each learner. Based on EEG data from 10 subjects, we created a prediction model that estimates the learner's workload to obtain an unobtrusive workload measure. Furthermore, we developed an interactive learning environment that uses the prediction model to estimate the learner's workload online based on the EEG data and adapt the difficulty of the learning material to keep the learner's workload in an optimal range. The EEG-based learning environment was used by 13 subjects to learn arithmetic addition in the octal number system, leading to a significant learning effect. The results suggest that it is feasible to use EEG as an unobtrusive measure of cognitive workload to adapt the learning content. Further it demonstrates that a promptly workload prediction is possible using a generalized prediction model without the need for a user-specific calibration.

  16. Three-Dimensional Engineered High Fidelity Normal Human Lung Tissue-Like Assemblies (TLA) as Targets for Human Respiratory Virus Infections

    NASA Technical Reports Server (NTRS)

    Goodwin, T. J.; Deatly, A. M.; Suderman, M. T.; Lin, Y.-H.; Chen, W.; Gupta, C. K.; Randolph, V. B.; Udem, S. A.

    2003-01-01

    Unlike traditional two-dimensional (2D) cell cultures, three-dimensional (3D) tissue-like assemblies (TLA) (Goodwin et aI, 1992, 1993, 2000 and Nickerson et aI. , 2001,2002) offer high organ fidelity with the potential to emulate the infective dynamics of viruses and bacteria in vivo. Thus, utilizing NASA micro gravity Rotating Wall Vessel (RWV) technology, in vitro human broncho-epithelial (HBE) TLAs were engineered to mimic in vivo tissue for study of human respiratory viruses. These 3D HBE TLAs were propagated from a human broncho-tracheal cell line with a mesenchymal component (HBTC) as the foundation matrix and either an adult human broncho-epithelial cell (BEAS-2B) or human neonatal epithelial cell (16HBE140-) as the overlying element. Resulting TLAs share several characteristic features with in vivo human respiratory epithelium including tight junctions, desmosomes and cilia (SEM, TEM). The presence of epithelium and specific lung epithelium markers furthers the contention that these HBE cells differentiate into TLAs paralleling in vivo tissues. A time course of infection of these 3D HBE TLAs with human respiratory syncytial virus (hRSV) wild type A2 strain, indicates that virus replication and virus budding are supported and manifested by increasing virus titer and detection of membrane-bound F and G glycoproteins. Infected 3D HBE TLAs remain intact for up to 12 days compared to infected 2D cultures that are destroyed in 2-3 days. Infected cells show an increased vacuolation and cellular destruction (by transmission electron microscopy) by day 9; whereas, uninfected cells remain robust and morphologically intact. Therefore, the 3D HBE TLAs mimic aspects of human respiratory epithelium providing a unique opportunity to analyze, for the first time, simulated in vivo viral infection independent of host immune response.

  17. Physical and mental workloads in professional dance teachers.

    PubMed

    Wanke, Eileen M; Schmidt, Mike; Leslie-Spinks, Jeremy; Fischer, Axel; Groneberg, David A

    2015-03-01

    The aim of this cross-sectional study was to investigate the level of mental and physical workloads in professional dance teachers depending on the trained students' age, technique level, or dance style. A total number of 133 professional dance pedagogues responded to an online cross-sectional questionnaire survey on self-assessment of physical and mental workloads occurring during dance units. The majority of dance teachers estimated their level of physical and mental workload to be almost as high as that of their students, with differences in physical and mental workloads observed depending on dance style, age of students, and technical level. More than 60% of the teachers were convinced that their occupation implies positive effects on their own health in terms of self-realization (78.2%), musculoskeletal system (66.9%), and social relationships (61.7%). Of all respondents, 58.6% stated that their musculoskeletal system was jeopardized by the physically demanding activity. This is followed by the fear of financial insecurity (50.4%). The majority of all dance teachers (males 65.4%, females 63.9%) would like to obtain further education on prevention against or dealing with physical workload. Physical and mental workloads play an important role in dance teaching. Coping with or preventing these loads could be keys to a lifelong, healthy career as a professional dance teacher. Future trials should look at clinical parameters of physical and mental load.

  18. Mental workload prediction based on attentional resource allocation and information processing.

    PubMed

    Xiao, Xu; Wanyan, Xiaoru; Zhuang, Damin

    2015-01-01

    Mental workload is an important component in complex human-machine systems. The limited applicability of empirical workload measures produces the need for workload modeling and prediction methods. In the present study, a mental workload prediction model is built on the basis of attentional resource allocation and information processing to ensure pilots' accuracy and speed in understanding large amounts of flight information on the cockpit display interface. Validation with an empirical study of an abnormal attitude recovery task showed that this model's prediction of mental workload highly correlated with experimental results. This mental workload prediction model provides a new tool for optimizing human factors interface design and reducing human errors.

  19. Workload measurement in a communication application operated through a P300-based brain-computer interface

    NASA Astrophysics Data System (ADS)

    Riccio, A.; Leotta, F.; Bianchi, L.; Aloise, F.; Zickler, C.; Hoogerwerf, E.-J.; Kübler, A.; Mattia, D.; Cincotti, F.

    2011-04-01

    Advancing the brain-computer interface (BCI) towards practical applications in technology-based assistive solutions for people with disabilities requires coping with problems of accessibility and usability to increase user acceptance and satisfaction. The main objective of this study was to introduce a usability-oriented approach in the assessment of BCI technology development by focusing on evaluation of the user's subjective workload and satisfaction. The secondary aim was to compare two applications for a P300-based BCI. Eight healthy subjects were asked to use an assistive technology solution which integrates the P300-based BCI with commercially available software under two conditions—visual stimuli needed to evoke the P300 response were either overlaid onto the application's graphical user interface or presented on a separate screen. The two conditions were compared for effectiveness (level of performance), efficiency (subjective workload measured by means of NASA-TXL) and satisfaction of the user. Although no significant difference in usability could be detected between the two conditions, the methodology proved to be an effective tool to highlight weaknesses in the technical solution.

  20. Orientations to Academic Workloads at Department Level

    ERIC Educational Resources Information Center

    Wolf, Amanda

    2010-01-01

    Universities confront many challenges in their efforts to manage staff activity with the aid of workload assessment and allocation systems. This article sets out fresh perspectives from an exploratory study designed to uncover patterns of subjective views about various aspects of workloads. Using Q methodology, academic staff in a single…

  1. Robotic assistance improves intracorporeal suturing performance and safety in the operating room while decreasing operator workload.

    PubMed

    Stefanidis, Dimitrios; Wang, Fikre; Korndorffer, James R; Dunne, J Bruce; Scott, Daniel J

    2010-02-01

    Intracorporeal suturing is one of the most difficult laparoscopic tasks. The purpose of this study was to assess the impact of robotic assistance on novice suturing performance, safety, and workload in the operating room. Medical students (n = 34), without prior laparoscopic suturing experience, were enrolled in an Institutional Review Board-approved, randomized protocol. After viewing an instructional video, subjects were tested in intracorporeal suturing on two identical, live, porcine Nissen fundoplication models; they placed three gastro-gastric sutures using conventional laparoscopic instruments in one model and using robotic assistance (da Vinci) in the other, in random order. Each knot was objectively scored based on time, accuracy, and security. Injuries to surrounding structures were recorded. Workload was assessed using the validated National Aeronautics and Space Administration (NASA) task load index (TLX) questionnaire, which measures the subjects' self-reported performance, effort, frustration, and mental, physical, and temporal demands of the task. Analysis was by paired t-test; p < 0.05 was considered significant. Compared with laparoscopy, robotic assistance enabled subjects to suture faster (595 +/- 22 s versus 459 +/- 137 s, respectively; p < 0.001), achieve higher overall scores (0 +/- 1 versus 95 +/- 128, respectively; p < 0.001), and commit fewer errors per knot (1.15 +/- 1.35 versus 0.05 +/- 0.26, respectively; p < 0.001). Subjects' overall score did not improve between the first and third attempt for laparoscopic suturing (0 +/- 0 versus 0 +/- 0; p = NS) but improved significantly for robotic suturing (49 +/- 100 versus 141 +/- 152; p < 0.001). Moreover, subjects indicated on the NASA-TLX scale that the task was more difficult to perform with laparoscopic instruments compared with robotic assistance (99 +/- 15 versus 57 +/- 23; p < 0.001). Compared with standard laparoscopy, robotic assistance significantly improved intracorporeal suturing

  2. Rework the workload.

    PubMed

    O'Bryan, Linda; Krueger, Janelle; Lusk, Ruth

    2002-03-01

    Kindred Healthcare, Inc., the nation's largest full-service network of long-term acute care hospitals, initiated a 3-year strategic plan to re-evaluate its workload management system. Here, follow the project's most important and difficult phase--designing and implementing the patient classification system.

  3. EEG-based workload estimation across affective contexts

    PubMed Central

    Mühl, Christian; Jeunet, Camille; Lotte, Fabien

    2014-01-01

    Workload estimation from electroencephalographic signals (EEG) offers a highly sensitive tool to adapt the human–computer interaction to the user state. To create systems that reliably work in the complexity of the real world, a robustness against contextual changes (e.g., mood), has to be achieved. To study the resilience of state-of-the-art EEG-based workload classification against stress we devise a novel experimental protocol, in which we manipulated the affective context (stressful/non-stressful) while the participant solved a task with two workload levels. We recorded self-ratings, behavior, and physiology from 24 participants to validate the protocol. We test the capability of different, subject-specific workload classifiers using either frequency-domain, time-domain, or both feature varieties to generalize across contexts. We show that the classifiers are able to transfer between affective contexts, though performance suffers independent of the used feature domain. However, cross-context training is a simple and powerful remedy allowing the extraction of features in all studied feature varieties that are more resilient to task-unrelated variations in signal characteristics. Especially for frequency-domain features, across-context training is leading to a performance comparable to within-context training and testing. We discuss the significance of the result for neurophysiology-based workload detection in particular and for the construction of reliable passive brain–computer interfaces in general. PMID:24971046

  4. Development of techniques for measuring pilot workload

    NASA Technical Reports Server (NTRS)

    Spyker, D. A.; Stackhouse, S. P.; Khalafalla, A. S.; Mclane, R. C.

    1971-01-01

    An objective method of assessing information workload based on physiological measurements was developed. Information workload, or reserve capacity, was measured using a visual discrimination secondary task and subjective rating of task difficulty. The primary task was two axis (pitch and roll) tracking, and the independent variables in this study were aircraft pitch dynamics and wind gust disturbances. The study was structured to provide: (1) a sensitive, nonloading measure of reserve capacity, and (2) an unencumbering reliable measurement of the psychophysiological state. From these, a measured workload index (MWI) and physiological workload index (PWI) were extracted. An important measure of the success of this study was the degree to which the MWI and PWI agreed across the 243 randomly-presented, four-minute trials (9 subjects X 9 tasks X 3 replications). The electrophysiological data collected included vectorcardiogaram, respiration, electromyogram, skin impedance, and electroencephalogram. Special computer programs were created for the analysis of each physiological variable. The digital data base then consisted of 82 physiological features for each of the 243 trials. A prediction of workload based on physiological observations was formulated as a simultaneous least-squares prediction problem. A best subset of 10 features was chosen to predict the three measures of reserve capacity. The cannonical correlation coefficient was .754 with a chi squared value of 91.3 which allows rejection of the null hypothesis with p of .995.

  5. A model for developing job rotation schedules that eliminate sequential high workloads and minimize between-worker variability in cumulative daily workloads: Application to automotive assembly lines.

    PubMed

    Yoon, Sang-Young; Ko, Jeonghan; Jung, Myung-Chul

    2016-07-01

    The aim of study is to suggest a job rotation schedule by developing a mathematical model in order to reduce cumulative workload from the successive use of the same body region. Workload assessment using rapid entire body assessment (REBA) was performed for the model in three automotive assembly lines of chassis, trim, and finishing to identify which body part exposed to relatively high workloads at workstations. The workloads were incorporated to the model to develop a job rotation schedule. The proposed schedules prevent the exposure to high workloads successively on the same body region and minimized between-worker variance in cumulative daily workload. Whereas some of workers were successively assigned to high workload workstation under no job rotation and serial job rotation. This model would help to reduce the potential for work-related musculoskeletal disorders (WMSDs) without additional cost for engineering work, although it may need more computational time and relative complex job rotation sequences. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  6. Benchmark Comparison of Dual- and Quad-Core Processor Linux Clusters with Two Global Climate Modeling Workloads

    NASA Technical Reports Server (NTRS)

    McGalliard, James

    2008-01-01

    This viewgraph presentation details the science and systems environments that NASA High End computing program serves. Included is a discussion of the workload that is involved in the processing for the Global Climate Modeling. The Goddard Earth Observing System Model, Version 5 (GEOS-5) is a system of models integrated using the Earth System Modeling Framework (ESMF). The GEOS-5 system was used for the Benchmark tests, and the results of the tests are shown and discussed. Tests were also run for the Cubed Sphere system, results for these test are also shown.

  7. The reliability and validity of flight task workload ratings

    NASA Technical Reports Server (NTRS)

    Childress, M. E.; Hart, S. G.; Bortolussi, M. R.

    1982-01-01

    Twelve instrument-rated general aviation pilots each flew two scenarios in a motion-base simulator. During each flight, the pilots verbally estimated their workload every three minutes. Following each flight, they again estimated workload for each flight segment and also rated their overall workload, perceived performance, and 13 specific factors on a bipolar scale. The results indicate that time (a priori, inflight, or postflight) of eliciting ratings, period to be covered by the ratings (a specific moment in time or a longer period), type of rating scale, and rating method (verbal, written, or other) may be important variables. Overall workload ratings appear to be predicted by different specific scales depending upon the situation, with activity level the best predictor. Perceived performance seems to bear little relationship to observer-rated performance when pilots rate their overall performance and an observer rates specific behaviors. Perceived workload and performance also seem unrelated.

  8. Voice-stress measure of mental workload

    NASA Technical Reports Server (NTRS)

    Alpert, Murray; Schneider, Sid J.

    1988-01-01

    In a planned experiment, male subjects between the age of 18 and 50 will be required to produce speech while performing various tasks. Analysis of the speech produced should reveal which aspects of voice prosody are associated with increased workloads. Preliminary results with two female subjects suggest a possible trend for voice frequency and amplitude to be higher and the variance of the voice frequency to be lower in the high workload condition.

  9. Predictive Features of a Cockpit Traffic Display: A Workload Assessment

    NASA Technical Reports Server (NTRS)

    Wickens, Christopher D.; Morphew, Ephimia

    1997-01-01

    Eighteen pilots flew a series of traffic avoidance maneuvers in an experiment designed to assess the support offered and workload imposed by different levels of traffic display information in a free flight simulation. Three display prototypes were compared which differed in traffic information provided. A BASELINE (BL) display provided current and (2nd order) predicted information regarding ownship and current information of an intruder aircraft, represented on lateral and vertical displays in a coplanar suite. An INTRUDER PREDICTOR (IP) display, augmented the baseline display by providing lateral and vertical prediction of the intruder aircraft. A THREAT VECTOR (TV) display added to the IP display a vector that indicates the direction from ownship to the intruder at the predicted point of closest contact (POCC). The length of the vector corresponds to the radius of the protected zone, and the distance of the intersection of the vector with ownship predictor, corresponds to the time available till POCC or loss of separation. Pilots time shared the traffic avoidance task with a secondary task requiring them to monitor the top of the display for faint targets. This task simulated the visual demands of out-of-cockpit scanning, and hence was used to estimate the head-down time required by the different display formats. The results revealed that both display augmentations improved performance (safety) as assessed by predicted and actual loss of separation (i.e., penetration of the protected zone). Both enhancements also reduced workload, as assessed by the NASA TLX scale. The intruder predictor display produced these benefits with no substantial impact on the qualitative nature of the avoidance maneuvers that were selected. The threat vector produced the safety benefits by inducing a greater degree of (effective) lateral maneuvering, thus partially offsetting the benefits of reduced workload. The three displays did not differ in terms of their effect on performance of

  10. Automation in clinical biochemistry: core, peripheral, STAT, and specialist laboratories in Australia.

    PubMed

    Streitberg, George S; Angel, Lyndall; Sikaris, Kenneth A; Bwititi, Phillip T

    2012-10-01

    Pathology has developed substantially since the 1990s with the introduction of total laboratory automation (TLA), in response to workloads and the need to improve quality. TLA has enhanced core laboratories, which evolved from discipline-based laboratories. Work practices have changed, with central reception now loading samples onto the Inlet module of the TLA. It is important to continually appraise technology. This study looked at the impact of technology using a self-administered survey to seniors in clinical biochemistry in NATA GX/GY-classified laboratories in Australia. The responses were yes, no, or not applicable and are expressed as percentages of responses. Some of the questions sourced for descriptive answers. Eighty-one laboratories responded, and the locations were 63%, 33%, and 4% in capital cities, regional cities, and country towns, respectively. Forty-two percent were public and 58% private. Clinical biochemistry was in all core laboratories of various sizes, and most performed up to 20 tests per sample. Thirty percent of the 121 surveyed laboratories had plans to install an automated line. Fifty-eight percent had hematology and biochemistry instrumentations in their peripheral laboratory, and 16% had a STAT laboratory on the same site as the core laboratory. There were varied instruments in specialist laboratories, and analyzers with embedded computers were in all laboratories. Medium and large laboratories had workstations with integrated instruments, and some large laboratories had TLA. Technology evolution and rising demand for pathology services make it imperative for laboratories to embrace such changes and reorganize the laboratories to take into account point-of-care testing and the efficiencies of core laboratories and TLA.

  11. Mobile Virtual Learning Object for the Assessment of Acute Pain as a Learning Tool to Assess Acute Pain in Nursing: An Analysis of the Mental Workload.

    PubMed

    Alvarez, Ana Graziela; Sasso, Grace; Iyengar, Sriram

    2015-11-06

    The inclusion of new technologies in education has motivated the development of studies on mental workload. These technologies are now being used in the teaching and learning process. The analysis enables identification of factors intervening in this workload as well as planning of overload prevention for educational activities using these technologies. To analyze the mental workload of an educational intervention with the Mobile Virtual Learning Object for the Assessment of Acute Pain in adults and newborns, according to the NASA Task Load Index criteria. A methodological study with data collected from 5 nurses and 75 students, from November of 2013 to February of 2014. The highest students' and specialists' means were in the dimensions of "Mental demand" (57.20 ± 22.27; 51 ± 29.45) and "Performance" (58.47 ± 24.19; 73 ± 28.85). The specialists' mental workload index was higher (50.20 ± 7.28) when compared with students' (47.87 ± 16.85) on a scale from 0 to 100 (P=.557). The instrument allowed for the assessment of mental workload after an online educational intervention with a mobile learning virtual object. An excessive overload was not identified among participants. Assessing mental workload from the use of educational technologies at the end of a task is a key to their applicability, with the aim of providing a more effective, stimulating, and long-lasting experience of the learning process.

  12. Mobile Virtual Learning Object for the Assessment of Acute Pain as a Learning Tool to Assess Acute Pain in Nursing: An Analysis of the Mental Workload

    PubMed Central

    2015-01-01

    Background The inclusion of new technologies in education has motivated the development of studies on mental workload. These technologies are now being used in the teaching and learning process. The analysis enables identification of factors intervening in this workload as well as planning of overload prevention for educational activities using these technologies. Objective To analyze the mental workload of an educational intervention with the Mobile Virtual Learning Object for the Assessment of Acute Pain in adults and newborns, according to the NASA Task Load Index criteria. Methods A methodological study with data collected from 5 nurses and 75 students, from November of 2013 to February of 2014. Results The highest students’ and specialists’ means were in the dimensions of “Mental demand” (57.20 ± 22.27; 51 ± 29.45) and “Performance” (58.47 ± 24.19; 73 ± 28.85). The specialists’ mental workload index was higher (50.20 ± 7.28) when compared with students’ (47.87 ± 16.85) on a scale from 0 to 100 (P=.557). Conclusions The instrument allowed for the assessment of mental workload after an online educational intervention with a mobile learning virtual object. An excessive overload was not identified among participants. Assessing mental workload from the use of educational technologies at the end of a task is a key to their applicability, with the aim of providing a more effective, stimulating, and long-lasting experience of the learning process. PMID:27731849

  13. Workload of Team Leaders and Team Members During a Simulated Sepsis Scenario.

    PubMed

    Tofil, Nancy M; Lin, Yiqun; Zhong, John; Peterson, Dawn Taylor; White, Marjorie Lee; Grant, Vincent; Grant, David J; Gottesman, Ronald; Sudikoff, Stephanie N; Adler, Mark; Marohn, Kimberly; Davidson, Jennifer; Cheng, Adam

    2017-09-01

    Crisis resource management principles dictate appropriate distribution of mental and/or physical workload so as not to overwhelm any one team member. Workload during pediatric emergencies is not well studied. The National Aeronautics and Space Administration-Task Load Index is a multidimensional tool designed to assess workload validated in multiple settings. Low workload is defined as less than 40, moderate 40-60, and greater than 60 signify high workloads. Our hypothesis is that workload among both team leaders and team members is moderate to high during a simulated pediatric sepsis scenario and that team leaders would have a higher workload than team members. Multicenter observational study. Nine pediatric simulation centers (five United States, three Canada, and one United Kingdom). Team leaders and team members during a 12-minute pediatric sepsis scenario. National Aeronautics and Space Administration-Task Load Index. One hundred twenty-seven teams were recruited from nine sites. One hundred twenty-seven team leaders and 253 team members completed the National Aeronautics and Space Administration-Task Load Index. Team leader had significantly higher overall workload than team member (51 ± 11 vs 44 ± 13; p < 0.01). Team leader had higher workloads in all subcategories except in performance where the values were equal and in physical demand where team members were higher than team leaders (29 ± 22 vs 18 ± 16; p < 0.01). The highest category for each group was mental 73 ± 13 for team leader and 60 ± 20 for team member. For team leader, two categories, mental (73 ± 17) and effort (66 ± 16), were high workload, most domains for team member were moderate workload levels. Team leader and team member are under moderate workloads during a pediatric sepsis scenario with team leader under high workloads (> 60) in the mental demand and effort subscales. Team leader average significantly higher workloads. Consideration of decreasing

  14. Effect of time span and task load on pilot mental workload

    NASA Technical Reports Server (NTRS)

    Berg, S. L.; Sheridan, T. B.

    1986-01-01

    Two sets of simulations designed to examine how a pilot's mental workload is affected by continuous manual-control activity versus discrete mental tasks that included the length of time between receiving an assignment and executing it are described. The first experiment evaluated two types of measures: objective performance indicators and subjective ratings. Subjective ratings for the two missions were different, but the objective performance measures were similar. In the second experiments, workload levels were increased and a second performance measure was taken. Mental workload had no influence on either performance-based workload measure. Subjective ratings discriminated among the scenarios and correlated with performance measures for high-workload flights. The number of mental tasks performed did not influence error rates, although high manual workloads did increase errors.

  15. New plasmid-mediated aminoglycoside 6'-N-acetyltransferase, AAC(6')-Ian, and ESBL, TLA-3, from a Serratia marcescens clinical isolate.

    PubMed

    Jin, Wanchun; Wachino, Jun-Ichi; Kimura, Kouji; Yamada, Keiko; Arakawa, Yoshichika

    2015-05-01

    Enterobacteriaceae clinical isolates showing amikacin resistance (MIC 64 to >256 mg/L) in the absence of 16S rRNA methyltransferase (MTase) genes were found. The aim of this study was to clarify the molecular mechanisms underlying amikacin resistance in Enterobacteriaceae clinical isolates that do not produce 16S rRNA MTases. PCR was performed to detect already-known amikacin resistance determinants. Cloning experiments and sequence analyses were performed to characterize unknown amikacin resistance determinants. Transfer of amikacin resistance determinants was performed by conjugation and transformation. The complete nucleotide sequence of the plasmids was determined by next-generation sequencing technology. Amikacin resistance enzymes were purified with a column chromatography system. The enzymatic function of the purified protein was investigated by thin-layer chromatography (TLC) and HPLC. Among the 14 isolates, 9 were found to carry already-known amikacin resistance determinants such as aac(6')-Ia and aac(6')-Ib. Genetic analyses revealed the presence of a new amikacin acetyltransferase gene, named aac(6')-Ian, located on a 169 829 bp transferable plasmid (p11663) of the Serratia marcescens strain NUBL-11663, one of the five strains negative for known aac(6') genes by PCR. Plasmid p11663 also carried a novel ESBL gene, named blaTLA-3. HPLC and TLC analyses demonstrated that AAC(6')-Ian catalysed the transfer of an acetyl group from acetyl coenzyme A onto an amine at the 6'-position of various aminoglycosides. We identified aac(6')-Ian as a novel amikacin resistance determinant together with a new ESBL gene, blaTLA-3, on a transferable plasmid of a S. marcescens clinical isolate. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. Driver distraction : eye glance analysis and conversation workload.

    DOT National Transportation Integrated Search

    2015-11-01

    The objective of this project was to assess the risk of performing a secondary task while driving a commercial : motor vehicle (CMV). The risk of conversation workload while driving a CMV was also assessed. Conversation : workload is a proxy for cogn...

  17. Using Neural Networks to Explore Air Traffic Controller Workload

    NASA Technical Reports Server (NTRS)

    Martin, Lynne; Kozon, Thomas; Verma, Savita; Lozito, Sandra C.

    2006-01-01

    When a new system, concept, or tool is proposed in the aviation domain, one concern is the impact that this will have on operator workload. As an experience, workload is difficult to measure in a way that will allow comparison of proposed systems with those already in existence. Chatterji and Sridhar (2001) suggested a method by which airspace parameters can be translated into workload ratings, using a neural network. This approach was employed, and modified to accept input from a non-real time airspace simulation model. The following sections describe the preparations and testing work that will enable comparison of a future airspace concept with a current day baseline in terms of workload levels.

  18. The dissociation of subjective measures of mental workload and performance

    NASA Technical Reports Server (NTRS)

    Yeh, Y. H.; Wickens, C. D.

    1984-01-01

    Dissociation between performance and subjective workload measures was investigated in the theoretical framework of the multiple resources model. Subjective measures do not preserve the vector characteristics in the multidimensional space described by the model. A theory of dissociation was proposed to locate the sources that may produce dissociation between the two workload measures. According to the theory, performance is affected by every aspect of processing whereas subjective workload is sensitive to the amount of aggregate resource investment and is dominated by the demands on the perceptual/central resources. The proposed theory was tested in three experiments. Results showed that performance improved but subjective workload was elevated with an increasing amount of resource investment. Furthermore, subjective workload was not as sensitive as was performance to differences in the amount of resource competition between two tasks. The demand on perceptual/central resources was found to be the most salient component of subjective workload. Dissociation occurred when the demand on this component was increased by the number of concurrent tasks or by the number of display elements. However, demands on response resources were weighted in subjective introspection as much as demands on perceptual/central resources. The implications of these results for workload practitioners are described.

  19. Three-Dimensional Human Bronchial-Tracheal Epithelial Tissue-Like Assemblies (TLAs) as Hosts for Severe Acute Respiratory Syndrome (SARS)-CoV Infection

    NASA Technical Reports Server (NTRS)

    Suderman, M. T.; McCarthy, M.; Mossell, E.; Watts, D. M.; Peters, C. J.; Shope, R.; Goodwin, T. J.

    2006-01-01

    A three-dimensional (3-D) tissue-like assembly (TLA) of human bronchial-tracheal mesenchymal (HBTC) cells with an overlay of human bronchial epithelial (BEAS-2B) cells was constructed using a NASA Bioreactor to survey the infectivity of SARS-CoV. This TLA was inoculated with a low passage number Urbani strain of SARS-CoV. At selected intervals over a 10-day period, media and cell aliquots of the 3-D TLA were harvested for viral titer assay and for light and electron microscopy examination. All viral titer assays were negative in both BEAS-2B two-dimensional monolayer and TLA. Light microscopy immunohistochemistry demonstrated antigen-antibody reactivity with anti-SARS-CoV polyclonal antibody to spike and nuclear proteins on cell membranes and cytoplasm. Coronavirus Group 2 cross-reactivity was demonstrated by positive reaction to anti-FIPV 1 and anti-FIPV 1 and 2 antibodies. TLA examination by transmission electron microscopy indicated increasing cytoplasmic vacuolation with numerous electron-dense bodies measuring 45 to 270 nm from days 4 through 10. There was no evidence of membrane blebbing, membrane duplication, or fragmentation of organelles in the TLAs. However, progressive disruption of endoplasmic reticulum was observed throughout the cells. Antibody response to SARS-CoV specific spike and nucleocapsid glycoproteins, cross-reactivity with FIPV antibodies, and the cytoplasmic pathology suggests this HBTE TLA model is permissive to SARS-CoV infection.

  20. Effects of digital altimetry on pilot workload

    NASA Technical Reports Server (NTRS)

    Harris, R. L., Sr.; Glover, B. J.

    1985-01-01

    A series of VOR-DME instrument landing approaches was flown in the DC-9 full-workload simulator to compare pilot performance, scan behavior, and workload when using a computer-drum-pointer altimeter (CDPA) and a digital altimeter (DA). Six pilots executed two sets of instrument landing approaches, with a CDPA on one set and a DA on the other set. Pilot scanning parameters, flight performance, and subjective opinion data were evaluated. It is found that the processes of gathering information from the CDPA and the DA are different. The DA requires a higher mental workload than the CDPA for a VOR-DME type landing approach. Mental processing of altitude information after transitioning back to the attitude indicator is more evident with the DA than with the CDPA.

  1. Cardiac-Activity Measures for Assessing Airport Ramp-Tower Controller's Workload

    NASA Technical Reports Server (NTRS)

    Hayashi, Miwa; Dulchinos, Victoria

    2016-01-01

    Heart rate (HR) and heart rate variability (HRV) potentially offer objective, continuous, and non-intrusive measures of human-operators mental workload. Such measurement capability is attractive for workload assessment in complex laboratory simulations or safety-critical field testing. The present study compares mean HR and HRV data with self-reported subjective workload ratings collected during a high-fidelity human-in-the-loop simulation of airport ramp traffic control operations, which involve complex cognitive and coordination tasks. Mean HR was found to be weakly sensitive to the workload ratings, while HRV was not sensitive or even contradictory to the assumptions. Until more knowledge on stress response mechanisms of the autonomic nervous system is obtained, it is recommended that these cardiac-activity measures be used with other workload assessment tools, such as subjective measures.

  2. Cardiac-Activity Measures for Assessing Airport Ramp-Tower Controller's Workload

    NASA Technical Reports Server (NTRS)

    Hayashi, Miwa; Dulchinos, Victoria L.

    2016-01-01

    Heart rate (HR) and heart rate variability (HRV) potentially offer objective, continuous, and non-intrusive measures of human-operator's mental workload. Such measurement capability is attractive for workload assessment in complex laboratory simulations or safety-critical field testing. The present study compares mean HR and HRV data with self-reported subjective workload ratings collected during a high-fidelity human-in-the-loop simulation of airport ramp traffic control operations, which involve complex cognitive and coordination tasks. Mean HR was found to be weakly sensitive to the workload ratings, while HRV was not sensitive or even contradictory to the assumptions. Until more knowledge on stress response mechanisms of the autonomic nervous system is obtained, it is recommended that these cardiac-activity measures be used with other workload assessment tools, such as subjective measures.

  3. CHROMagar Orientation Medium Reduces Urine Culture Workload

    PubMed Central

    Manickam, Kanchana; Karlowsky, James A.; Adam, Heather; Lagacé-Wiens, Philippe R. S.; Rendina, Assunta; Pang, Paulette; Murray, Brenda-Lee

    2013-01-01

    Microbiology laboratories continually strive to streamline and improve their urine culture algorithms because of the high volumes of urine specimens they receive and the modest numbers of those specimens that are ultimately considered clinically significant. In the current study, we quantitatively measured the impact of the introduction of CHROMagar Orientation (CO) medium into routine use in two hospital laboratories and compared it to conventional culture on blood and MacConkey agars. Based on data extracted from our Laboratory Information System from 2006 to 2011, the use of CO medium resulted in a 28% reduction in workload for additional procedures such as Gram stains, subcultures, identification panels, agglutination tests, and biochemical tests. The average number of workload units (one workload unit equals 1 min of hands-on labor) per urine specimen was significantly reduced (P < 0.0001; 95% confidence interval [CI], 0.5326 to 1.047) from 2.67 in 2006 (preimplementation of CO medium) to 1.88 in 2011 (postimplementation of CO medium). We conclude that the use of CO medium streamlined the urine culture process and increased bench throughput by reducing both workload and turnaround time in our laboratories. PMID:23363839

  4. Associations between attending physician workload, teaching effectiveness, and patient safety.

    PubMed

    Wingo, Majken T; Halvorsen, Andrew J; Beckman, Thomas J; Johnson, Matthew G; Reed, Darcy A

    2016-03-01

    Prior studies suggest that high workload among attending physicians may be associated with reduced teaching effectiveness and poor patient outcomes, but these relationships have not been investigated using objective measures of workload and safety. To examine associations between attending workload, teaching effectiveness, and patient safety, hypothesizing that higher workload would be associated with lower teaching effectiveness and negative patient outcomes. We conducted a retrospective study of 69,386 teaching evaluation items submitted by 543 internal medicine residents for 107 attending physicians who supervised inpatient teaching services from July 2, 2005 to July 1, 2011. Attending workload measures included hospital service census, patient length of stay, daily admissions, daily discharges, and concurrent outpatient duties. Teaching effectiveness was measured using residents' evaluations of attendings. Patient outcomes considered were applicable patient safety indicators (PSIs), intensive care unit transfers, cardiopulmonary resuscitation/rapid response team calls, and patient deaths. Mixed linear models and generalized linear regression models were used for statistical analysis. Workload measures of midnight census and daily discharges were associated with lower teaching evaluation scores (both β = -0.026, P < 0.0001). The number of daily admissions was associated with higher teaching scores (β = 0.021, P = 0.001) and increased PSIs (odds ratio = 1.81, P = 0.0001). Several measures of attending physician workload were associated with slightly lower teaching effectiveness, and patient safety may be compromised when teams are managing new admissions. Ongoing efforts by residency programs to optimize the learning environment should include strategies to manage the workload of supervising attendings. © 2016 Society of Hospital Medicine.

  5. Crew procedures and workload of retrofit concepts for microwave landing system

    NASA Technical Reports Server (NTRS)

    Summers, Leland G.; Jonsson, Jon E.

    1989-01-01

    Crew procedures and workload for Microwave Landing Systems (MLS) that could be retrofitted into existing transport aircraft were evaluated. Two MLS receiver concepts were developed. One is capable of capturing a runway centerline and the other is capable of capturing a segmented approach path. Crew procedures were identified and crew task analyses were performed using each concept. Crew workload comparisons were made between the MLS concepts and an ILS baseline using a task-timeline workload model. Workload indexes were obtained for each scenario. The results showed that workload was comparable to the ILS baseline for the MLS centerline capture concept, but significantly higher for the segmented path capture concept.

  6. Submegabase Clusters of Unstable Tandem Repeats Unique to the Tla Region of Mouse T Haplotypes

    PubMed Central

    Uehara, H.; Ebersole, T.; Bennett, D.; Artzt, K.

    1990-01-01

    We describe here the identification and genomic organization of mouse t haplotype-specific elements (TSEs) 7.8 and 5.8 kb in length. The TSEs exist as submegabase-long clusters of tandem repeats localized in the Tla region of the major histocompatibility complex of all t haplotype chromosomes examined. In contrast, no such clusters were detected among 12 inbred strains of Mus musculus and other Mus species; thus, clusters of TSEs represent the first absolutely qualitative difference between t haplotypes and wild-type chromosomes. Pulsed field gel electrophoresis shows that the number of clusters, and the number of repeats in each cluster are extremely variable. Dramatic quantitative differences of TSEs uniquely distinguish every independent t haplotype from any other. The complete nucleotide sequence of one 7.8-kb TSE reveals significant homology to the ETn (a major transcript in the early embryo of the mouse), and some homologies to intracisternal A-particles and the mammary tumor virus env gene. Apart from the diagnostic relevance to t haplotypes, evolutionary and functional significances are discussed with respect to chromosome structure and genetic recombination. PMID:2076812

  7. A computerized multidimensional measurement of mental workload via handwriting analysis.

    PubMed

    Luria, Gil; Rosenblum, Sara

    2012-06-01

    The goal of this study was to test the effect of mental workload on handwriting behavior and to identify characteristics of low versus high mental workload in handwriting. We hypothesized differences between handwriting under three different load conditions and tried to establish a profile that integrated these indicators. Fifty-six participants wrote three numerical progressions of varying difficulty on a digitizer attached to a computer so that we could evaluate their handwriting behavior. Differences were found in temporal, spatial, and angular velocity handwriting measures, but no significant differences were found for pressure measures. Using data reduction, we identified three clusters of handwriting, two of which differentiated well according to the three mental workload conditions. We concluded that handwriting behavior is affected by mental workload and that each measure provides distinct information, so that they present a comprehensive indicator of mental workload.

  8. Using Psychophysiological Sensors to Assess Mental Workload During Web Browsing.

    PubMed

    Jimenez-Molina, Angel; Retamal, Cristian; Lira, Hernan

    2018-02-03

    Knowledge of the mental workload induced by a Web page is essential for improving users' browsing experience. However, continuously assessing the mental workload during a browsing task is challenging. To address this issue, this paper leverages the correlation between stimuli and physiological responses, which are measured with high-frequency, non-invasive psychophysiological sensors during very short span windows. An experiment was conducted to identify levels of mental workload through the analysis of pupil dilation measured by an eye-tracking sensor. In addition, a method was developed to classify mental workload by appropriately combining different signals (electrodermal activity (EDA), electrocardiogram, photoplethysmo-graphy (PPG), electroencephalogram (EEG), temperature and pupil dilation) obtained with non-invasive psychophysiological sensors. The results show that the Web browsing task involves four levels of mental workload. Also, by combining all the sensors, the efficiency of the classification reaches 93.7%.

  9. Assessment of operators' mental workload using physiological and subjective measures in cement, city traffic and power plant control centers.

    PubMed

    Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji

    2016-01-01

    The present study aimed to evaluate the operators' mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628,P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. The results suggested that when operators' mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions.

  10. I/O Performance Characterization of Lustre and NASA Applications on Pleiades

    NASA Technical Reports Server (NTRS)

    Saini, Subhash; Rappleye, Jason; Chang, Johnny; Barker, David Peter; Biswas, Rupak; Mehrotra, Piyush

    2012-01-01

    In this paper we study the performance of the Lustre file system using five scientific and engineering applications representative of NASA workload on large-scale supercomputing systems such as NASA s Pleiades. In order to facilitate the collection of Lustre performance metrics, we have developed a software tool that exports a wide variety of client and server-side metrics using SGI's Performance Co-Pilot (PCP), and generates a human readable report on key metrics at the end of a batch job. These performance metrics are (a) amount of data read and written, (b) number of files opened and closed, and (c) remote procedure call (RPC) size distribution (4 KB to 1024 KB, in powers of 2) for I/O operations. RPC size distribution measures the efficiency of the Lustre client and can pinpoint problems such as small write sizes, disk fragmentation, etc. These extracted statistics are useful in determining the I/O pattern of the application and can assist in identifying possible improvements for users applications. Information on the number of file operations enables a scientist to optimize the I/O performance of their applications. Amount of I/O data helps users choose the optimal stripe size and stripe count to enhance I/O performance. In this paper, we demonstrate the usefulness of this tool on Pleiades for five production quality NASA scientific and engineering applications. We compare the latency of read and write operations under Lustre to that with NFS by tracing system calls and signals. We also investigate the read and write policies and study the effect of page cache size on I/O operations. We examine the performance impact of Lustre stripe size and stripe count along with performance evaluation of file per process and single shared file accessed by all the processes for NASA workload using parameterized IOR benchmark.

  11. Performance evaluation of the NASA/KSC CAD/CAE and office automation LAN's

    NASA Technical Reports Server (NTRS)

    Zobrist, George W.

    1994-01-01

    This study's objective is the performance evaluation of the existing CAD/CAE (Computer Aided Design/Computer Aided Engineering) network at NASA/KSC. This evaluation also includes a similar study of the Office Automation network, since it is being planned to integrate this network into the CAD/CAE network. The Microsoft mail facility which is presently on the CAD/CAE network was monitored to determine its present usage. This performance evaluation of the various networks will aid the NASA/KSC network managers in planning for the integration of future workload requirements into the CAD/CAE network and determining the effectiveness of the planned FDDI (Fiber Distributed Data Interface) migration.

  12. Cognitive Workload and Sleep Restriction Interact to Influence Sleep Homeostatic Responses

    PubMed Central

    Goel, Namni; Abe, Takashi; Braun, Marcia E.; Dinges, David F.

    2014-01-01

    Study Objectives: Determine the effects of high versus moderate workload on sleep physiology and neurobehavioral measures, during sleep restriction (SR) and no sleep restriction (NSR) conditions. Design: Ten-night experiment involving cognitive workload and SR manipulations. Setting: Controlled laboratory environment. Participants: Sixty-three healthy adults (mean ± standard deviation: 33.2 ± 8.7 y; 29 females), age 22–50 y. Interventions: Following three baseline 8 h time in bed (TIB) nights, subjects were randomized to one of four conditions: high cognitive workload (HW) + SR; moderate cognitive workload (MW) + SR; HW + NSR; or MW + NSR. SR entailed 5 consecutive nights at 4 h TIB; NSR entailed 5 consecutive nights at 8 h TIB. Subjects received three workload test sessions/day consisting of 15-min preworkload assessments, followed by a 60-min (MW) or 120-min (HW) workload manipulation comprised of visually based cognitive tasks, and concluding with 15-min of postworkload assessments. Experimental nights were followed by two 8-h TIB recovery sleep nights. Polysomnography was collected on baseline night 3, experimental nights 1, 4, and 5, and recovery night 1 using three channels (central, frontal, occipital [C3, Fz, O2]). Measurements and Results: High workload, regardless of sleep duration, increased subjective fatigue and sleepiness (all P < 0.05). In contrast, sleep restriction produced cumulative increases in Psychomotor Vigilance Test (PVT) lapses, fatigue, and sleepiness and decreases in PVT response speed and Maintenance of Wakefulness Test (MWT) sleep onset latencies (all P < 0.05). High workload produced longer sleep onset latencies (P < 0.05, d = 0.63) and less wake after sleep onset (P < 0.05, d = 0.64) than moderate workload. Slow-wave energy—the putative marker of sleep homeostasis—was higher at O2 than C3 only in the HW + SR condition (P < 0.05). Conclusions: High cognitive workload delayed sleep onset, but it also promoted sleep homeostatic

  13. The effect of augmented real-time image guidance on task workload during endoscopic sinus surgery.

    PubMed

    Dixon, Benjamin J; Chan, Harley; Daly, Michael J; Vescan, Allan D; Witterick, Ian J; Irish, Jonathan C

    2012-01-01

    Due to proximity to critical structures, the need for spatial awareness during endoscopic sinus surgery (ESS) is essential. We have developed an augmented, real-time image-guided surgery (ART-IGS) system that provides live navigational data and proximity alerts to the operating surgeon during ablation. We wished to test the hypothesis that task workload would be reduced when using this technology. A trial involved 8 otolaryngology residents and fellows performing ESS on cadaveric specimens; 1 side in a conventional method (control) and 1 side with ART-IGS. After computed tomography scanning, anatomical contouring, and registration of the head, a three-dimensional (3D) virtual endoscopic view, ablative tool tracking, and proximity alerts were enabled. Each subject completed ESS tasks and rated their workload during and after the exercise using the National Aeronautics and Space Administration (NASA) Task Load Index (TLX). A questionnaire and open feedback interview were completed after the procedure. There was a significant reduction in mental demand, temporal demand, effort, and frustration when using the ART-IGS system in comparison to the control (p < 0.02). Perceived performance was increased (p = 0.02). Most subjects agreed that the system was sufficiently accurate, caused minimal interruption, and increased confidence. Optical tracking line-of-sight issues were frequently cited as the main limitation early in the study; however, this was largely resolved. ART-IGS reduces task workload for trainees performing ESS. Live navigation and alert zones may be a valuable intraoperative teaching aid. Copyright © 2012 American Rhinologic Society-American Academy of Otolaryngic Allergy, LLC.

  14. "Time Is Not Enough." Workload in Higher Education: A Student Perspective

    ERIC Educational Resources Information Center

    Kyndt, Eva; Berghmans, Inneke; Dochy, Filip; Bulckens, Lydwin

    2014-01-01

    Students' workload has been recognised as a major factor in the teaching and learning environment. This paper starts by structuring the different conceptualisations of workload described in the scientific literature. Besides the traditional distinction between objective and subjective or perceived workload, a distinction between conceptualisations…

  15. Development of a Methodology for Assessing Aircrew Workloads.

    DTIC Science & Technology

    1981-11-01

    Workload Feasibility Study. .. ...... 52 Subjects. .. .............. ........ 53 Equipment .. ............... ....... 53 Date Analysis ... analysis ; simulation; standard time systems; switching synthetic time systems; task activities; task interference; time study; tracking; workload; work sampl...standard data systems, information content analysis , work sampling and job evaluation. Con- ventional methods were found to be deficient in accounting

  16. GPs’ perceptions of workload in England: a qualitative interview study

    PubMed Central

    Croxson, Caroline HD; Ashdown, Helen F; Hobbs, FD Richard

    2017-01-01

    Background GPs report the lowest levels of morale among doctors, job satisfaction is low, and the GP workforce is diminishing. Workload is frequently cited as negatively impacting on commitment to a career in general practice, and many GPs report that their workload is unmanageable. Aim To gather an in-depth understanding of GPs’ perceptions and attitudes towards workload. Design and setting All GPs working within NHS England were eligible. Advertisements were circulated via regional GP e-mail lists and national social media networks in June 2015. Of those GPs who responded, a maximum-variation sample was selected until data saturation was reached. Method Semi-structured, qualitative interviews were conducted. Data were analysed thematically. Results In total, 171 GPs responded, and 34 were included in this study. GPs described an increase in workload over recent years, with current working days being long and intense, raising concerns over the wellbeing of GPs and patients. Full-time partnership was generally not considered to be possible, and many participants felt workload was unsustainable, particularly given the diminishing workforce. Four major themes emerged to explain increased workload: increased patient needs and expectations; a changing relationship between primary and secondary care; bureaucracy and resources; and the balance of workload within a practice. Continuity of care was perceived as being eroded by changes in contracts and working patterns to deal with workload. Conclusion This study highlights the urgent need to address perceived lack of investment and clinical capacity in general practice, and suggests that managing patient expectations around what primary care can deliver, and reducing bureaucracy, have become key issues, at least until capacity issues are resolved. PMID:28093422

  17. GPs' perceptions of workload in England: a qualitative interview study.

    PubMed

    Croxson, Caroline Hd; Ashdown, Helen F; Hobbs, Fd Richard

    2017-02-01

    GPs report the lowest levels of morale among doctors, job satisfaction is low, and the GP workforce is diminishing. Workload is frequently cited as negatively impacting on commitment to a career in general practice, and many GPs report that their workload is unmanageable. To gather an in-depth understanding of GPs' perceptions and attitudes towards workload. All GPs working within NHS England were eligible. Advertisements were circulated via regional GP e-mail lists and national social media networks in June 2015. Of those GPs who responded, a maximum-variation sample was selected until data saturation was reached. Semi-structured, qualitative interviews were conducted. Data were analysed thematically. In total, 171 GPs responded, and 34 were included in this study. GPs described an increase in workload over recent years, with current working days being long and intense, raising concerns over the wellbeing of GPs and patients. Full-time partnership was generally not considered to be possible, and many participants felt workload was unsustainable, particularly given the diminishing workforce. Four major themes emerged to explain increased workload: increased patient needs and expectations; a changing relationship between primary and secondary care; bureaucracy and resources; and the balance of workload within a practice. Continuity of care was perceived as being eroded by changes in contracts and working patterns to deal with workload. This study highlights the urgent need to address perceived lack of investment and clinical capacity in general practice, and suggests that managing patient expectations around what primary care can deliver, and reducing bureaucracy, have become key issues, at least until capacity issues are resolved. © British Journal of General Practice 2017.

  18. Using Psychophysiological Sensors to Assess Mental Workload During Web Browsing

    PubMed Central

    Jimenez-Molina, Angel; Retamal, Cristian; Lira, Hernan

    2018-01-01

    Knowledge of the mental workload induced by a Web page is essential for improving users’ browsing experience. However, continuously assessing the mental workload during a browsing task is challenging. To address this issue, this paper leverages the correlation between stimuli and physiological responses, which are measured with high-frequency, non-invasive psychophysiological sensors during very short span windows. An experiment was conducted to identify levels of mental workload through the analysis of pupil dilation measured by an eye-tracking sensor. In addition, a method was developed to classify mental workload by appropriately combining different signals (electrodermal activity (EDA), electrocardiogram, photoplethysmo-graphy (PPG), electroencephalogram (EEG), temperature and pupil dilation) obtained with non-invasive psychophysiological sensors. The results show that the Web browsing task involves four levels of mental workload. Also, by combining all the sensors, the efficiency of the classification reaches 93.7%. PMID:29401688

  19. Application and Validation of Workload Assessment Techniques

    DTIC Science & Technology

    1993-03-01

    tech ical report documents the process and outcome of meeting this objective. Procedure: A series of eight separate studies was conducted using three...development process . The task analysis and simulation technique was shown to have the capability to track empirical workload ratings. More research is...operator workload during the systems acquisi- tion process , and (b) a pamphlet for the managers of Army systems that describes the need and some procedures

  20. How the workload impacts on cognitive cooperation: A pilot study.

    PubMed

    Sciaraffa, Nicolina; Borghini, Gianluca; Arico, Pietro; Di Flumeri, Gianluca; Toppi, Jlenia; Colosimo, Alfredo; Bezerianos, Anastatios; Thakor, Nitish V; Babiloni, Fabio

    2017-07-01

    Cooperation degradation can be seen as one of the main causes of human errors. Poor cooperation could arise from aberrant mental processes, such as mental overload, that negatively affect the user's performance. Using different levels of difficulty in a cooperative task, we combined behavioural, subjective and neurophysiological data with the aim to i) quantify the mental workload under which the crew was operating, ii) evaluate the degree of their cooperation, and iii) assess the impact of the workload demands on the cooperation levels. The combination of such data showed that high workload demand impacted significantly on the performance, workload perception, and degree of cooperation.

  1. Training and testing ERP-BCIs under different mental workload conditions

    NASA Astrophysics Data System (ADS)

    Ke, Yufeng; Wang, Peiyuan; Chen, Yuqian; Gu, Bin; Qi, Hongzhi; Zhou, Peng; Ming, Dong

    2016-02-01

    Objective. As one of the most popular and extensively studied paradigms of brain-computer interfaces (BCIs), event-related potential-based BCIs (ERP-BCIs) are usually built and tested in ideal laboratory settings in most existing studies, with subjects concentrating on stimuli and intentionally avoiding possible distractors. This study is aimed at examining the effect of simultaneous mental activities on ERP-BCIs by manipulating various levels of mental workload during the training and/or testing of an ERP-BCI. Approach. Mental workload was manipulated during the training or testing of a row-column P300-speller to investigate how and to what extent the spelling performance and the ERPs evoked by the oddball stimuli are affected by simultaneous mental workload. Main results. Responses of certain ERP components, temporal-occipital N200 and the late reorienting negativity evoked by the oddball stimuli and the classifiability of ERP features between targets and non-targets decreased with the increase of mental workload encountered by the subject. However, the effect of mental workload on the performance of ERP-BCI was not always negative but depended on the conditions where the ERP-BCI was built and applied. The performance of ERP-BCI built under an ideal lab setting without any irrelevant mental activities declined with the increasing mental workload of the testing data. However, the performance was significantly improved when an ERP-BCI was built under an appropriate mental workload level, compared to that built under speller-only conditions. Significance. The adverse effect of concurrent mental activities may present a challenge for ERP-BCIs trained in ideal lab settings but which are to be used in daily work, especially when users are performing demanding mental processing. On the other hand, the positive effects of the mental workload of the training data suggest that introducing appropriate mental workload during training ERP-BCIs is of potential benefit to the

  2. Operator strategies under varying conditions of workload

    NASA Technical Reports Server (NTRS)

    Arnegard, Ruth J.

    1991-01-01

    An attempt was made to operationally define and measure strategic behavior in a complex multiple task environment. The Multi-Attribute Task battery was developed to simulate various aspects of flight and consisted of an auditory communication task, monitoring tasks, a tracking tasks, a resource management task which allowed a wide range of responding patterns, and a scheduling window which allowed operators to predict changes in workload. This battery was validated for its sensitivity to strategic behavior, and baseline measures for each individual task were collected. Twenty-four undergraduate and graduate students then performed the battery for four 64 minute sessions which took place over a period of 2 days. Each subject performed the task battery under four levels of workload, which were presented for equal lengths of time during all four sessions. Results indicated that in general, performance improves as a function of experience with the battery, but that performance decreased as workload level increased. The data also showed that subjects developed strategies for responding to the resource management task which allowed them to manage the high workload levels more efficiently. This particular strategy developed over time but was also associated with errors of complacency. These results are presented along with implications for the aviation field and areas of future research.

  3. Pilot Mental Workload with Predictive System Status Information

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.

    1998-01-01

    Research has shown a strong pilot preference for predictive information of aircraft system status in the flight deck. However, the mental workload associated with using this predictive information has not been ascertained. The study described here attempted to measure mental workload. In this simulator experiment, three types of predictive information (none, whether a parameter was changing abnormally, and the time for a parameter to reach an alert range) and four initial times to a parameter alert range (1 minute, 5 minutes, 15 minutes, and ETA+45 minutes) were tested to determine their effects on subjects mental workload. Subjective workload ratings increased with increasing predictive information (whether a parameter was changing abnormally or the time for a parameter to reach an alert range). Subjective situation awareness decreased with more predictive information but it became greater with increasing initial times to a parameter alert range. Also, subjective focus changed depending on the type of predictive information. Lastly, skin temperature fluctuated less as the initial time to a parameter alert range increased.

  4. Workload Characterization of a Leadership Class Storage Cluster

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Youngjae; Gunasekaran, Raghul; Shipman, Galen M

    2010-01-01

    Understanding workload characteristics is critical for optimizing and improving the performance of current systems and software, and architecting new storage systems based on observed workload patterns. In this paper, we characterize the scientific workloads of the world s fastest HPC (High Performance Computing) storage cluster, Spider, at the Oak Ridge Leadership Computing Facility (OLCF). Spider provides an aggregate bandwidth of over 240 GB/s with over 10 petabytes of RAID 6 formatted capacity. OLCFs flagship petascale simulation platform, Jaguar, and other large HPC clusters, in total over 250 thousands compute cores, depend on Spider for their I/O needs. We characterize themore » system utilization, the demands of reads and writes, idle time, and the distribution of read requests to write requests for the storage system observed over a period of 6 months. From this study we develop synthesized workloads and we show that the read and write I/O bandwidth usage as well as the inter-arrival time of requests can be modeled as a Pareto distribution.« less

  5. Student Burnout as a Function of Personality, Social Support, and Workload.

    ERIC Educational Resources Information Center

    Jacobs, Sheri R.; Dodd, David K.

    2003-01-01

    Measures of social support, personality, and workload were related to psychological burnout among 149 college students. High levels of burnout were predicted by negative temperament and subjective workload, but actual workload (academic and vocational) had little to do with burnout. Low levels of burnout were predicted by positive temperament,…

  6. Automation - Changes in cognitive demands and mental workload

    NASA Technical Reports Server (NTRS)

    Tsang, Pamela S.; Johnson, Walter W.

    1987-01-01

    The effect of partial automation on mental workloads in man/machine tasks is investigated experimentally. Subjective workload measures are obtained from six subjects after performance of a task battery comprising two manual (flight-path control, FC, and target acquisition, TA) tasks and one decisionmaking (engine failure, EF) task; the FC task was performed in both a fully manual (altitude and lateral control) mode and in a semiautomated mode (autmatic latitude control). The performance results and subjective evaluations are presented in graphs and characterized in detail. The automation is shown to improve objective performance and lower subjective workload significantly in the combined FC/TA task, but not in the FC task alone or in the FC/EF task.

  7. The relationship between physical workload and quality within line-based assembly.

    PubMed

    Ivarsson, Anna; Eek, Frida

    2016-07-01

    Reducing costs and improvement of product quality are considered important to ensure productivity within a company. Quality deviations during production processes and ergonomics have previously shown to be associated. This study explored the relationship between physical workload and real (found during production processes) and potential (need of extra time and assistance to complete tasks) quality deviations in a line-based assembly plant. The physical workload on and the work rotation between 52 workstations were assessed. As the outcome, real and potential quality deviations were studied during 10 weeks. Results show that workstations with higher physical workload had significantly more real deviations compared to lower workload stations. Static work posture had significantly more potential deviations. Rotation between high and low workload was related to fewer quality deviations compared to rotation between only high workload stations. In conclusion, physical ergonomics seems to be related to real and potential quality deviation within line-based assembly. Practitioner Summary: To ensure good productivity in manufacturing industries, it is important to reduce costs and improve product quality. This study shows that high physical workload is associated with quality deviations and need of extra time and assistance to complete tasks within line-based assembly, which can be financially expensive for a company.

  8. Exploring the Utility of Workload Models in Academe: A Pilot Study

    ERIC Educational Resources Information Center

    Boyd, Leanne

    2014-01-01

    The workload of academics in Australia is increasing. Among the potential ramifications of this are work-related stress and burnout. Unions have negotiated workload models in employment agreements as a means of distributing workload in a fair and transparent manner. This qualitative pilot study aimed to explore how academics perceive their current…

  9. EFFECTIVE INDICES FOR MONITORING MENTAL WORKLOAD WHILE PERFORMING MULTIPLE TASKS.

    PubMed

    Hsu, Bin-Wei; Wang, Mao-Jiun J; Chen, Chi-Yuan; Chen, Fang

    2015-08-01

    This study identified several physiological indices that can accurately monitor mental workload while participants performed multiple tasks with the strategy of maintaining stable performance and maximizing accuracy. Thirty male participants completed three 10-min. simulated multitasks: MATB (Multi-Attribute Task Battery) with three workload levels. Twenty-five commonly used mental workload measures were collected, including heart rate, 12 HRV (heart rate variability), 10 EEG (electroencephalography) indices (α, β, θ, α/θ, θ/β from O1-O2 and F4-C4), and two subjective measures. Analyses of index sensitivity showed that two EEG indices, θ and α/θ (F4-C4), one time-domain HRV-SDNN (standard deviation of inter-beat intervals), and four frequency-domain HRV: VLF (very low frequency), LF (low frequency), %HF (percentage of high frequency), and LF/HF were sensitive to differentiate high workload. EEG α/θ (F4-C4) and LF/HF were most effective for monitoring high mental workload. LF/HF showed the highest correlations with other physiological indices. EEG α/θ (F4-C4) showed strong correlations with subjective measures across different mental workload levels. Operation strategy would affect the sensitivity of EEG α (F4-C4) and HF.

  10. Measuring Mental Workload: A Performance Battery.

    DTIC Science & Technology

    1987-09-01

    1982). Subjective mental workload. Human Factors, 24, 25-40. Neisser , U ., Novick, R., & Lazar, R. (1963). Searching for ten targets 0...818 MES~A [G MENTAL WORKLOAD: A PERFORMANCE BATTERY( U ) 1/ • i NUN ENGINEERING LAS ABERDEEN PROVING GROUND MO L A MHITAKER ET AL .EP 87 HEL-TH-21-87...UNCLASSIFIED FG 5/9IIEEEEEEIE EhhIEllE~lllEE I.E.E.E I1.2 P e- - ,uIII j .. - - I ,,, 65 -S S p *q 0 0 0 0 0 0 0 0 0 u -; 5 . . ~qqr AD-A187 118

  11. Internal consistency and validity of a new physical workload questionnaire

    PubMed Central

    Bot, S; Terwee, C; van der Windt, D A W M; Feleus, A; Bierma-Zeinstra, S; Knol, D; Bouter, L; Dekker, J

    2004-01-01

    Aims: To examine the dimensionality, internal consistency, and construct validity of a new physical workload questionnaire in employees with musculoskeletal complaints. Methods: Factor analysis was applied to the responses in three study populations with musculoskeletal disorders (n = 406, 300, and 557) on 26 items related to physical workload. The internal consistency of the resulting subscales was examined. It was hypothesised that physical workload would vary among different occupational groups. The occupations of all subjects were classified into four groups on the basis of expected workload (heavy physical load; long lasting postures and repetitive movements; both; no physical load). Construct validity of the subscales created was tested by comparing the subscale scores among these occupational groups. Results: The pattern of the factor loadings of items was almost identical for the three study populations. Two interpretable factors were found: items related to heavy physical workload loaded highly on the first factor, and items related to static postures or repetitive work loaded highly on the second factor. The first constructed subscale "heavy physical work" had a Cronbach's α of 0.92 to 0.93 and the second subscale "long lasting postures and repetitive movements", of 0.86 to 0.87. Six of eight hypotheses regarding the construct validity of the subscales were confirmed. Conclusions: The results support the internal structure, internal consistency, and validity of the new physical workload questionnaire. Testing this questionnaire in non-symptomatic employees and comparing its performance with objective assessments of physical workload are important next steps in the validation process. PMID:15550603

  12. Psychophysiological response to cognitive workload during symmetrical, asymmetrical and dual-task walking.

    PubMed

    Knaepen, Kristel; Marusic, Uros; Crea, Simona; Rodríguez Guerrero, Carlos D; Vitiello, Nicola; Pattyn, Nathalie; Mairesse, Olivier; Lefeber, Dirk; Meeusen, Romain

    2015-04-01

    Walking with a lower limb prosthesis comes at a high cognitive workload for amputees, possibly affecting their mobility, safety and independency. A biocooperative prosthesis which is able to reduce the cognitive workload of walking could offer a solution. Therefore, we wanted to investigate whether different levels of cognitive workload can be assessed during symmetrical, asymmetrical and dual-task walking and to identify which parameters are the most sensitive. Twenty-four healthy subjects participated in this study. Cognitive workload was assessed through psychophysiological responses, physical and cognitive performance and subjective ratings. The results showed that breathing frequency and heart rate significantly increased, and heart rate variability significantly decreased with increasing cognitive workload during walking (p<.05). Performance measures (e.g., cadence) only changed under high cognitive workload. As a result, psychophysiological measures are the most sensitive to identify changes in cognitive workload during walking. These parameters reflect the cognitive effort necessary to maintain performance during complex walking and can easily be assessed regardless of the task. This makes them excellent candidates to feed to the control loop of a biocooperative prosthesis in order to detect the cognitive workload. This information can then be used to adapt the robotic assistance to the patient's cognitive abilities. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Patient transfers in Australia: implications for nursing workload and patient outcomes.

    PubMed

    Blay, Nicole; Duffield, Christine M; Gallagher, Robyn

    2012-04-01

    To discuss the impact of patient transfers on patient outcomes and nursing workload. Many patient transfers are essential and occur in response to patients' clinical changes. However, increasingly within Australia transfers are performed in response to reductions in bed numbers, resulting in 'bed block'. A discussion of the literature related to inpatient transfers, nursing workload and patient safety. Measures to increase patient flow such as short-stay units may result in an increase in patient transfers and nursing workload. Frequent patient transfers may also increase the risk of medication incidents, health-care acquired infections and patient falls. The continuing demand for health care has led to a reactionary bed management system that, in an attempt to accommodate patients, has resulted in increased transfers between wards. This can have a negative effect on nursing workload and affect patient outcomes. High nursing workload is cited as one reason for nurses leaving the profession. Reductions in non-essential transfers may reduce nurse workload, improve patient outcomes and enhance continuity of patient care. © 2011 Blackwell Publishing Ltd.

  14. [Variability in nursing workload within Swiss Diagnosis Related Groups].

    PubMed

    Baumberger, Dieter; Bürgin, Reto; Bartholomeyczik, Sabine

    2014-04-01

    Nursing care inputs represent one of the major cost components in the Swiss Diagnosis Related Group (DRG) structure. High and low nursing workloads in individual cases are supposed to balance out via the DRG group. Research results indicating possible problems in this area cannot be reliably extrapolated to SwissDRG. An analysis of nursing workload figures with DRG indicators was carried out in order to decide whether there is a need to develop SwissDRG classification criteria that are specific to nursing care. The case groups were determined with SwissDRG 0.1, and nursing workload with LEP Nursing 2. Robust statistical methods were used. The evaluation of classification accuracy was carried out with R2 as the measurement of variance reduction and the coefficient of homogeneity (CH). To ensure reliable conclusions, statistical tests with bootstrapping methods were performed. The sample included 213 groups with a total of 73930 cases from ten hospitals. The DRG classification was seen to have limited explanatory power for variability in nursing workload inputs, both for all cases (R2 = 0.16) and for inliers (R2 = 0.32). Nursing workload homogeneity was statistically significant unsatisfactory (CH < 0.67) in 123 groups, including 24 groups in which it was significant defective (CH < 0.60). Therefore, there is a high risk of high and low nursing workloads not balancing out in these groups, and, as a result, of financial resources being wrongly allocated. The development of nursing-care-specific SwissDRG classification criteria for improved homogeneity and variance reduction is therefore indicated.

  15. [Evaluation of nurse workload in patients undergoing therapeutic hypothermia].

    PubMed

    Argibay-Lago, Ana; Fernández-Rodríguez, Diego; Ferrer-Sala, Nuria; Prieto-Robles, Cristina; Hernanz-del Río, Alexandre; Castro-Rebollo, Pedro

    2014-01-01

    Therapeutic hypothermia (TH) is recommended to minimize neurological damage in patients surviving sudden cardiac arrest (SCA). There is scarcity of data evaluating the nursing workload in these patients. The objective of the study is to assess the workload of nurses whilst treating patients undergoing TH after SCA. A 43-month prospective-retrospective comparative cohort study was designed. Patients admitted to intensive care unit, for recovered SCA and persistent coma, were included. A comparison was made using the baseline characteristics, medical management, in-hospital mortality, and nursing workload during the first 96hours using the Therapeutic Intervention Scoring System-28 (TISS-28); Nursing Activities Score (NAS); and Nine Equivalents of Nursing Manpower Use Score (NEMS) scales among patients who received TH and those who did not. A total 46 patients were included: 26 in the TH group and 20 in the Non-TH group. Regarding baseline characteristics and management, the TH group presented higher prevalence of smoking habit (69 vs. 25%, p=0.012), out-of-hospital SCA (96 vs. 55%, p<0.001), and the performance of coronary angiography (96 vs. 65%, p=0.014) compared with the non-TH group. No differences were observed in the nursing workload, assessed by TISS 28, NAS or NEMS scales, or in-hospital mortality. In this study performance of TH in SCA survivors is not associated with an increase in nursing workload. The installation of a TH program does not require the use of more nursing resources in terms of workload. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  16. The psychometrics of mental workload: multiple measures are sensitive but divergent.

    PubMed

    Matthews, Gerald; Reinerman-Jones, Lauren E; Barber, Daniel J; Abich, Julian

    2015-02-01

    A study was run to test the sensitivity of multiple workload indices to the differing cognitive demands of four military monitoring task scenarios and to investigate relationships between indices. Various psychophysiological indices of mental workload exhibit sensitivity to task factors. However, the psychometric properties of multiple indices, including the extent to which they intercorrelate, have not been adequately investigated. One hundred fifty participants performed in four task scenarios based on a simulation of unmanned ground vehicle operation. Scenarios required threat detection and/or change detection. Both single- and dual-task scenarios were used. Workload metrics for each scenario were derived from the electroencephalogram (EEG), electrocardiogram, transcranial Doppler sonography, functional near infrared, and eye tracking. Subjective workload was also assessed. Several metrics showed sensitivity to the differing demands of the four scenarios. Eye fixation duration and the Task Load Index metric derived from EEG were diagnostic of single-versus dual-task performance. Several other metrics differentiated the two single tasks but were less effective in differentiating single- from dual-task performance. Psychometric analyses confirmed the reliability of individual metrics but failed to identify any general workload factor. An analysis of difference scores between low- and high-workload conditions suggested an effort factor defined by heart rate variability and frontal cortex oxygenation. General workload is not well defined psychometrically, although various individual metrics may satisfy conventional criteria for workload assessment. Practitioners should exercise caution in using multiple metrics that may not correspond well, especially at the level of the individual operator.

  17. Assessment of operators’ mental workload using physiological and subjective measures in cement, city traffic and power plant control centers

    PubMed Central

    Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji

    2016-01-01

    Background: The present study aimed to evaluate the operators’ mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. Methods: This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. Results: The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628,P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. Conclusion: The results suggested that when operators’ mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions. PMID:27386425

  18. Training and subjective workload in a category search task

    NASA Technical Reports Server (NTRS)

    Vidulich, Michael A.; Pandit, Parimal

    1986-01-01

    This study examined automaticity as a means by which training influences mental workload. Two groups were trained in a category search task. One group received a training paradigm designed to promote the development of automaticity; the other group received a training paradigm designed to prohibit it. Resultant performance data showed the expected improvement as a result of the development of automaticity. Subjective workload assessments mirrored the performance results in most respects. The results supported the position that subjective mental workload assessments may be sensitive to the effect of training when it produces a lower level of cognitive load.

  19. Psychophysiological measures of cognitive workload in laboratory and flight

    NASA Technical Reports Server (NTRS)

    Wilson, Glenn F.; Badeau, Albert

    1993-01-01

    Psychophysiological data have been recorded during different levels of cognitive workload in laboratory and flight settings. Cardiac, eye blink, and brain data have shown meaningful changes as a function of the levels of mental workload. Increased cognitive workload is generally associated with increased heart rates, decreased blink rates and eye closures, and decreased evoked potential amplitudes. However, comparisons of laboratory and flight data show that direct transference of laboratory findings to the flight environment is not possible in many cases. While the laboratory data are valuable, a data base from flight is required so that 'real world' data can be properly interpreted.

  20. Classification Systems for Individual Differences in Multiple-task Performance and Subjective Estimates of Workload

    NASA Technical Reports Server (NTRS)

    Damos, D. L.

    1984-01-01

    Human factors practitioners often are concerned with mental workload in multiple-task situations. Investigations of these situations have demonstrated repeatedly that individuals differ in their subjective estimates of workload. These differences may be attributed in part to individual differences in definitions of workload. However, after allowing for differences in the definition of workload, there are still unexplained individual differences in workload ratings. The relation between individual differences in multiple-task performance, subjective estimates of workload, information processing abilities, and the Type A personality trait were examined.

  1. Event-related potential indices of workload in a single task paradigm

    NASA Technical Reports Server (NTRS)

    Horst, R. L.; Munson, R. C.; Ruchkin, D. S.

    1984-01-01

    Many previous studies of both behavioral and physiological correlates of cognitive workload have burdened subjects with a contrived secondary task in order to assess the workload of a primary task. The present study investigated event-related potential (ERP) indices of workload in a single task paradigm. Subjects monitored changing digital readouts for values that went 'out-of-bounds'. The amplitude of a long-latency positivity in the ERPs elicited by readout changes increased with the number of readouts being monitored. This effect of workload on ERPs is reported, along with plans for additional analyses to address theoretical implications.

  2. An Application-Based Performance Evaluation of NASAs Nebula Cloud Computing Platform

    NASA Technical Reports Server (NTRS)

    Saini, Subhash; Heistand, Steve; Jin, Haoqiang; Chang, Johnny; Hood, Robert T.; Mehrotra, Piyush; Biswas, Rupak

    2012-01-01

    The high performance computing (HPC) community has shown tremendous interest in exploring cloud computing as it promises high potential. In this paper, we examine the feasibility, performance, and scalability of production quality scientific and engineering applications of interest to NASA on NASA's cloud computing platform, called Nebula, hosted at Ames Research Center. This work represents the comprehensive evaluation of Nebula using NUTTCP, HPCC, NPB, I/O, and MPI function benchmarks as well as four applications representative of the NASA HPC workload. Specifically, we compare Nebula performance on some of these benchmarks and applications to that of NASA s Pleiades supercomputer, a traditional HPC system. We also investigate the impact of virtIO and jumbo frames on interconnect performance. Overall results indicate that on Nebula (i) virtIO and jumbo frames improve network bandwidth by a factor of 5x, (ii) there is a significant virtualization layer overhead of about 10% to 25%, (iii) write performance is lower by a factor of 25x, (iv) latency for short MPI messages is very high, and (v) overall performance is 15% to 48% lower than that on Pleiades for NASA HPC applications. We also comment on the usability of the cloud platform.

  3. Virtual automation.

    PubMed

    Casis, E; Garrido, A; Uranga, B; Vives, A; Zufiaurre, C

    2001-01-01

    Total laboratory automation (TLA) can be substituted in mid-size laboratories by a computer sample workflow control (virtual automation). Such a solution has been implemented in our laboratory using PSM, software developed in cooperation with Roche Diagnostics (Barcelona, Spain), to this purpose. This software is connected to the online analyzers and to the laboratory information system and is able to control and direct the samples working as an intermediate station. The only difference with TLA is the replacement of transport belts by personnel of the laboratory. The implementation of this virtual automation system has allowed us the achievement of the main advantages of TLA: workload increase (64%) with reduction in the cost per test (43%), significant reduction in the number of biochemistry primary tubes (from 8 to 2), less aliquoting (from 600 to 100 samples/day), automation of functional testing, drastic reduction of preanalytical errors (from 11.7 to 0.4% of the tubes) and better total response time for both inpatients (from up to 48 hours to up to 4 hours) and outpatients (from up to 10 days to up to 48 hours). As an additional advantage, virtual automation could be implemented without hardware investment and significant headcount reduction (15% in our lab).

  4. Subjective scaling of mental workload in a multi-task environment

    NASA Technical Reports Server (NTRS)

    Daryanian, B.

    1982-01-01

    Those factors in a multi-task environment that contribute to the operators' "sense" of mental workload were identified. The subjective judgment as conscious experience of mental effort was decided to be the appropriate method of measurement. Thurstone's law of comparative judgment was employed in order to construct interval scales of subjective mental workload from paired comparisons data. An experimental paradigm (Simulated Multi-Task Decision-Making Environment) was employed to represent the ideal experimentally controlled environment in which human operators were asked to "attend" to different cases of Tulga's decision making tasks. Through various statistical analyses it was found that, in general, a lower number of tasks-to-be-processed per unit time (a condition associated with longer interarrival times), results in a lower mental workload, a higher consistency of judgments within a subject, a higher degree of agreement among the subjects, and larger distances between the cases on the Thurstone scale of subjective mental workload. The effects of various control variables and their interactions, and the different characteristics of the subjects on the variation of subjective mental workload are demonstrated.

  5. Quantifying the Workload of Subject Bibliographers in Collection Development.

    ERIC Educational Resources Information Center

    Metz, Paul

    1991-01-01

    Discussion of the role of subject bibliographers in collection development activities focuses on an approach developed at Virginia Polytechnic and State Institute to provide a formula for estimating the collection development workload of subject bibliographers. Workload standards and matrix models of organizational structures are discussed, and…

  6. Nurse-patient assignment models considering patient acuity metrics and nurses' perceived workload.

    PubMed

    Sir, Mustafa Y; Dundar, Bayram; Barker Steege, Linsey M; Pasupathy, Kalyan S

    2015-06-01

    Patient classification systems (PCSs) are commonly used in nursing units to assess how many nursing care hours are needed to care for patients. These systems then provide staffing and nurse-patient assignment recommendations for a given patient census based on these acuity scores. Our hypothesis is that such systems do not accurately capture workload and we conduct an experiment to test this hypothesis. Specifically, we conducted a survey study to capture nurses' perception of workload in an inpatient unit. Forty five nurses from oncology and surgery units completed the survey and rated the impact of patient acuity indicators on their perceived workload using a six-point Likert scale. These ratings were used to calculate a workload score for an individual nurse given a set of patient acuity indicators. The approach offers optimization models (prescriptive analytics), which use patient acuity indicators from a commercial PCS as well as a survey-based nurse workload score. The models assign patients to nurses in a balanced manner by distributing acuity scores from the PCS and survey-based perceived workload. Numerical results suggest that the proposed nurse-patient assignment models achieve a balanced assignment and lower overall survey-based perceived workload compared to the assignment based solely on acuity scores from the PCS. This results in an improvement of perceived workload that is upwards of five percent. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. All Things Being Equal: Observing Australian Individual Academic Workloads

    ERIC Educational Resources Information Center

    Dobele, Angela; Rundle-Thiele, Sharyn; Kopanidis, Foula; Steel, Marion

    2010-01-01

    The achievement of greater gender equity within Australian universities is a significant issue for both the quality and the strength of Australian higher education. This paper contributes to our knowledge of academic workloads, observing individual workloads in business faculties. A multiple case study method was employed to observe individual…

  8. Measurement, Modeling, and Analysis of a Large-scale Blog Sever Workload

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeon, Myeongjae; Hwang, Jeaho; Kim, Youngjae

    2010-01-01

    Despite the growing popularity of Online Social Networks (OSNs), the workload characteristics of OSN servers, such as those hosting blog services, are not well understood. Understanding workload characteristics is important for opti- mizing and improving the performance of current systems and software based on observed trends. Thus, in this paper, we characterize the system workload of the largest blog hosting servers in South Korea, Tistory1. In addition to understanding the system workload of the blog hosting server, we have developed synthesized workloads and obtained the following major findings: (i) the transfer size of non-multimedia files and blog articles can bemore » modeled by a truncated Pareto distribution and a log-normal distribution respectively, and (ii) users accesses to blog articles do not show temporal locality, but they are strongly biased toward those posted along with images or audio.« less

  9. Workload and associated factors: a study in maritime port in Brazil.

    PubMed

    Cezar-Vaz, Marta Regina; Bonow, Clarice Alves; Almeida, Marlise Capa Verde de; Sant'Anna, Cynthia Fontella; Cardoso, Leticia Silveira

    2016-11-28

    to identify the effect of the mental, physical, temporal, performance, total effort and frustration demands in the overall workload, and in the same way analyze the global burden of port labor and associated factors that contribute most to their decrease or increase. a cross-sectional, quantitative study, developed with 232 dock workers. For data collection, a structured questionnaire with descriptive, occupational, smoking and illicit drug use variables was applied, as well as variables on the load on the tasks undertaken at work, based on the questionnaire NASA Task Load Index. For data analysis, we used the analysis of the Poisson regression model. the demands physical demand and total effort showed greater effect on the overall workload, indicating high overall load on port work (134 employees - 58.8%). The following remained associated statistically with high levels of workload: age (p = 0.044), to be employee of the wharfage (p = 0.006), work only at night (p = 0.025), smoking (p = 0.037) and use of illegal drugs (p = 0.029). the workload in this type of activity was high, and the professional category and work shift the factors that contributed to the increase, while the age proved to be a factor associated with a decrease. identificar o efeito das demandas mental, física, temporal, de desempenho, esforço total e frustração na carga global de trabalho, da mesma maneira que analisar a carga global de trabalho portuário e fatores associados que mais contribuem para sua diminuição ou aumento. estudo transversal, quantitativo, desenvolvido com 232 trabalhadores portuários. Para a coleta de dados, foi aplicado um questionário estruturado com variáveis de caracterização, ocupacional, tabagismo e uso de drogas ilícitas, além de variáveis sobre a carga nas tarefas desenvolvidas no trabalho, com base no questionário NASA Task Load Index. Para análise dos dados, utilizou-se a análise do modelo de regressão de Poisson. as demandas exigência f

  10. Approximate entropy: a new evaluation approach of mental workload under multitask conditions

    NASA Astrophysics Data System (ADS)

    Yao, Lei; Li, Xiaoling; Wang, Wei; Dong, Yuanzhe; Jiang, Ying

    2014-04-01

    There are numerous instruments and an abundance of complex information in the traditional cockpit display-control system, and pilots require a long time to familiarize themselves with the cockpit interface. This can cause accidents when they cope with emergency events, suggesting that it is necessary to evaluate pilot cognitive workload. In order to establish a simplified method to evaluate cognitive workload under a multitask condition. We designed a series of experiments involving different instrument panels and collected electroencephalograms (EEG) from 10 healthy volunteers. The data were classified and analyzed with an approximate entropy (ApEn) signal processing. ApEn increased with increasing experiment difficulty, suggesting that it can be used to evaluate cognitive workload. Our results demonstrate that ApEn can be used as an evaluation criteria of cognitive workload and has good specificity and sensitivity. Moreover, we determined an empirical formula to assess the cognitive workload interval, which can simplify cognitive workload evaluation under multitask conditions.

  11. Effect of time span and task load on pilot mental workload

    NASA Technical Reports Server (NTRS)

    Berg, S. L.; Sheridan, T. B.

    1985-01-01

    Two sets of experiments were run to examine how the mental workload of a pilot might be measured. The effects of continuous manual control activity versus discrete assigned mental tasks (including the length of time between receiving an assignment and executing it) were examined. The first experiment evaluated the strengths and weaknesses of measuring mental workload with an objective perforamance (altitude deviations) and five subjective ratings (activity level, complexity, difficulty, stress, and workload). The second set of experiments built upon the first set by increasing workload intensities and adding another performance measure: airspeed deviation. The results are discussed for both low and high experience pilots.

  12. Spikes in acute workload are associated with increased injury risk in elite cricket fast bowlers.

    PubMed

    Hulin, Billy T; Gabbett, Tim J; Blanch, Peter; Chapman, Paul; Bailey, David; Orchard, John W

    2014-04-01

    To determine if the comparison of acute and chronic workload is associated with increased injury risk in elite cricket fast bowlers. Data were collected from 28 fast bowlers who completed a total of 43 individual seasons over a 6-year period. Workloads were estimated by summarising the total number of balls bowled per week (external workload), and by multiplying the session rating of perceived exertion by the session duration (internal workload). One-week data (acute workload), together with 4-week rolling average data (chronic workload), were calculated for external and internal workloads. The size of the acute workload in relation to the chronic workload provided either a negative or positive training-stress balance. A negative training-stress balance was associated with an increased risk of injury in the week after exposure, for internal workload (relative risk (RR)=2.2 (CI 1.91 to 2.53), p=0.009), and external workload (RR=2.1 (CI 1.81 to 2.44), p=0.01). Fast bowlers with an internal workload training-stress balance of greater than 200% had a RR of injury of 4.5 (CI 3.43 to 5.90, p=0.009) compared with those with a training-stress balance between 50% and 99%. Fast bowlers with an external workload training-stress balance of more than 200% had a RR of injury of 3.3 (CI 1.50 to 7.25, p=0.033) in comparison to fast bowlers with an external workload training-stress balance between 50% and 99%. These findings demonstrate that large increases in acute workload are associated with increased injury risk in elite cricket fast bowlers.

  13. Balancing nurses' workload in hospital wards: study protocol of developing a method to manage workload.

    PubMed

    van den Oetelaar, W F J M; van Stel, H F; van Rhenen, W; Stellato, R K; Grolman, W

    2016-11-10

    Hospitals pursue different goals at the same time: excellent service to their patients, good quality care, operational excellence, retaining employees. This requires a good balance between patient needs and nursing staff. One way to ensure a proper fit between patient needs and nursing staff is to work with a workload management method. In our view, a nursing workload management method needs to have the following characteristics: easy to interpret; limited additional registration; applicable to different types of hospital wards; supported by nurses; covers all activities of nurses and suitable for prospective planning of nursing staff. At present, no such method is available. The research follows several steps to come to a workload management method for staff nurses. First, a list of patient characteristics relevant to care time will be composed by performing a Delphi study among staff nurses. Next, a time study of nurses' activities will be carried out. The 2 can be combined to estimate care time per patient group and estimate the time nurses spend on non-patient-related activities. These 2 estimates can be combined and compared with available nursing resources: this gives an estimate of nurses' workload. The research will take place in an academic hospital in the Netherlands. 6 surgical wards will be included, capacity 15-30 beds. The study protocol was submitted to the Medical Ethical Review Board of the University Medical Center (UMC) Utrecht and received a positive advice, protocol number 14-165/C. This method will be developed in close cooperation with staff nurses and ward management. The strong involvement of the end users will contribute to a broader support of the results. The method we will develop may also be useful for planning purposes; this is a strong advantage compared with existing methods, which tend to focus on retrospective analysis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

  14. The Electric Speaking Practice: A Telephone Workload Study

    PubMed Central

    Westbury, R. C.

    1974-01-01

    The telephone workload in a family practice was studied for two recording periods separated by a 12 month interval. A record was kept of the number of calls, their length, the day of the week on which they were made, to whom they were made, and for what purpose. The telephone practice accounts for about 20 percent of the total practice workload. Calls to the patients and to their representatives were about equally common and account for most of the workload, but a large amount of telephone work is devoted to ‘backing up’ these direct contacts. The use of the telephone for medical purposes saves much time for the patients and much money for the paying agency. A plea is made for intensive study of this aspect of family medicine. PMID:20469032

  15. Subjective workload and individual differences in information processing abilities

    NASA Technical Reports Server (NTRS)

    Damos, D. L.

    1984-01-01

    This paper describes several experiments examining the source of individual differences in the experience of mental workload. Three sources of such differences were examined: information processing abilities, timesharing abilities, and personality traits/behavior patterns. On the whole, there was little evidence that individual differences in information processing abilities or timesharing abilities are related to perceived differences in mental workload. However, individuals with strong Type A coronary prone behavior patterns differed in both single- and multiple-task performance from individuals who showed little evidence of such a pattern. Additionally, individuals with a strong Type A pattern showed some dissociation between objective performance and the experience of mental workload.

  16. Voice measures of workload in the advanced flight deck

    NASA Technical Reports Server (NTRS)

    Schneider, Sid J.; Alpert, Murray; Odonnell, Richard

    1989-01-01

    Voice samples were obtained from 14 male subjects under high and low workload conditions. Acoustical analysis of the voice suggested that high workload conditions can be revealed by their effects on the voice over time. Aircrews in the advanced flight deck will be voicing short, imperative sentences repeatedly. A drop in the energy of the voice, as reflected by reductions in amplitude and frequency over time, and the failure to achieve old amplitude and frequency levels after rest periods, can signal that the workload demands of the situation are straining the speaker. This kind of measurement would be relatively unaffected by individual differences in acoustical measures.

  17. Neutron beam irradiation study of workload dependence of SER in a microprocessor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Michalak, Sarah E; Graves, Todd L; Hong, Ted

    It is known that workloads are an important factor in soft error rates (SER), but it is proving difficult to find differentiating workloads for microprocessors. We have performed neutron beam irradiation studies of a commercial microprocessor under a wide variety of workload conditions from idle, performing no operations, to very busy workloads resembling real HPC, graphics, and business applications. There is evidence that the mean times to first indication of failure, MTFIF defined in Section II, may be different for some of the applications.

  18. Human interaction with robotic systems: performance and workload evaluations.

    PubMed

    Reinerman-Jones, L; Barber, D J; Szalma, J L; Hancock, P A

    2017-10-01

    We first tested the effect of differing tactile informational forms (i.e. directional cues vs. static cues vs. dynamic cues) on objective performance and perceived workload in a collaborative human-robot task. A second experiment evaluated the influence of task load and informational message type (i.e. single words vs. grouped phrases) on that same collaborative task. In both experiments, the relationship of personal characteristics (attentional control and spatial ability) to performance and workload was also measured. In addition to objective performance and self-report of cognitive load, we evaluated different physiological responses in each experiment. Results showed a performance-workload association for directional cues, message type and task load. EEG measures however, proved generally insensitive to such task load manipulations. Where significant EEG effects were observed, right hemisphere amplitude differences predominated, although unexpectedly these latter relationships were negative. Although EEG measures were partially associated with performance, they appear to possess limited utility as measures of workload in association with tactile displays. Practitioner Summary: As practitioners look to take advantage of innovative tactile displays in complex operational realms like human-robotic interaction, associated performance effects are mediated by cognitive workload. Despite some patterns of association, reliable reflections of operator state can be difficult to discern and employ as the number, complexity and sophistication of these respective measures themselves increase.

  19. Mental workload measurement for emergency operating procedures in digital nuclear power plants.

    PubMed

    Gao, Qin; Wang, Yang; Song, Fei; Li, Zhizhong; Dong, Xiaolu

    2013-01-01

    Mental workload is a major consideration for the design of emergency operation procedures (EOPs) in nuclear power plants. Continuous and objective measures are desired. This paper compares seven mental workload measurement methods (pupil size, blink rate, blink duration, heart rate variability, parasympathetic/sympathetic ratio, total power and (Goals, Operations, Methods, and Section Rules)-(Keystroke Level Model) GOMS-KLM-based workload index) with regard to sensitivity, validity and intrusiveness. Eighteen participants performed two computerised EOPs of different complexity levels, and mental workload measures were collected during the experiment. The results show that the blink rate is sensitive to both the difference in the overall task complexity and changes in peak complexity within EOPs, that the error rate is sensitive to the level of arousal and correlate to the step error rate and that blink duration increases over the task period in both low and high complexity EOPs. Cardiac measures were able to distinguish tasks with different overall complexity. The intrusiveness of the physiological instruments is acceptable. Finally, the six physiological measures were integrated using group method of data handling to predict perceived overall mental workload. The study compared seven measures for evaluating the mental workload with emergency operation procedure in nuclear power plants. An experiment with simulated procedures was carried out, and the results show that eye response measures are useful for assessing temporal changes of workload whereas cardiac measures are useful for evaluating the overall workload.

  20. Pilot workload and fatigue: A critical survey of concepts and assessment techniques

    NASA Technical Reports Server (NTRS)

    Gartner, W. B.; Murphy, M. R.

    1976-01-01

    The principal unresolved issues in conceptualizing and measuring pilot workload and fatigue are discussed. These issues are seen as limiting the development of more useful working concepts and techniques and their application to systems engineering and management activities. A conceptual analysis of pilot workload and fatigue, an overview and critique of approaches to the assessment of these phenomena, and a discussion of current trends in the management of unwanted workload and fatigue effects are presented. Refinements and innovations in assessment methods are recommended for enhancing the practical significance of workload and fatigue studies.

  1. Flight Test Assessments of Pilot Workload, System Usability, and Situation Awareness of TASAR

    NASA Technical Reports Server (NTRS)

    Burke, Kelly A.; Haynes, Mark A.

    2016-01-01

    Traffic Aware Strategic Aircrew Requests (TASAR) is an onboard automation concept intended to identify trajectory optimizations, in terms of fuel and time saving objectives, clear of known traffic, weather, and airspace restrictions prior to the aircrew initiating a route-change request to Air Traffic Control (ATC). The software implementation of the TASAR concept is the Traffic Aware Planner (TAP). TASAR analysis and development is being executed by the NASA Langley Research Center's Crew Systems and Aviation Operations Branch (CSAOB) under the sponsorship of the Airspace Technology Demonstration (ATD) Project of the NASA Airspace Operations and Safety Program (AOSP). The TASAR Flight Trial-2 (FT-2) was conducted in June, 2015 out of the Newport News/Williamsburg International Airport. This flight trial was conducted using a Piaggio Avanti flight test aircraft and consisted of 12 Evaluation Flights with airline commercial pilots participating as the Evaluation Pilots, three destination airports in Atlanta and Jacksonville Air Route Traffic Control Centers, and one pair of flight plans associated with each destination airport. The primary goal of FT-2 was to reduce risk for upcoming operational trials with NASA partner airlines, Alaska Airlines and Virgin America. To accomplish this primary goal, six independent objectives were conducted during FT-2, however, this paper will report only the findings of Objective 5; the assessment of system usability, pilot perceived workload, and the degree of pilot acceptability of the TAP Human Machine Interface (HMI) during flight operations, via the administration of several subjective measures.

  2. Assessment of nursing workload in adult psychiatric inpatient units: a scoping review.

    PubMed

    Sousa, C; Seabra, P

    2018-05-16

    No systematic reviews on measurement tools in adult psychiatric inpatient settings exist in the literature, and thus, further research is required on ways to identify approaches to calculate safe nurse staffing levels based on patients' care needs in adult psychiatric inpatient units. To identify instruments that enable an assessment of nursing workload in psychiatric settings. Method A scoping review was conducted. Four studies were identified, with five instruments used to support the calculation of staff needs and workload. All four studies present methodological limitations. Two instruments have already been adapted to this specific context, but validation studies are lacking. The findings indicate that the tools used to evaluate nursing workload in these settings require further development, with the concomitant need for more research to clarify the definition of nursing workload as well as to identify factors with the greatest impact on nursing workload. This review highlights the need to develop tools to assess workload in psychiatric inpatient units that embrace patient-related and non-patient-related activities. The great challenge is to enable a sensitive perception of workload resulting from nurses' psychotherapeutic interventions, an important component of treatment for many patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. Pilot Workload Measurement and Experience on Supersonic Cruise Aircraft

    NASA Technical Reports Server (NTRS)

    Rezek, T. W.

    1978-01-01

    Aircraft parameters and physiological parameters most indicative of crew workload were investigated. Recommendations were used to form the basis for a continuing study in which variations of the interval between heart beats are used as a measure of nonphysical workload. Preliminary results are presented and current efforts in further defining this physiological measure are outlined.

  4. Dissociation of performance and subjective measures of workload

    NASA Technical Reports Server (NTRS)

    Yeh, Yei-Yu; Wickens, Christopher D.

    1988-01-01

    A theory is presented to identify sources that produce dissociations between performance and subjective measures of workload. The theory states that performance is determined by (1) amount of resources invested, (2) resource efficiency, and (3) degree of competition for common resources in a multidimensional space described in the multiple-resources model. Subjective perception of workload, multidimensional in nature, increases with greater amounts of resource investment and with greater demands on working memory. Performance and subjective workload measures dissociate when greater resources are invested to improve performance of a resource-limited task; when demands on working memory are increased by time-sharing between concurrent tasks or between display elements; and when performance is sensitive to resource competition and subjective measures are more sensitive to total investment. These dissociation findings and their implications are discussed and directions for future research are suggested.

  5. Improved lower extremity pedaling mechanics in individuals with stroke under maximal workloads.

    PubMed

    Linder, Susan M; Rosenfeldt, Anson B; Bazyk, Andrew S; Koop, Mandy Miller; Ozinga, Sarah; Alberts, Jay L

    2018-05-01

    Background Individuals with stroke present with motor control deficits resulting in the abnormal activation and timing of agonist and antagonist muscles and inefficient movement patterns. The analysis of pedaling biomechanics provides a window into understanding motor control deficits, which vary as a function of workload. Understanding the relationship between workload and motor control is critical when considering exercise prescription during stroke rehabilitation. Objectives To characterize pedaling kinematics and motor control processes under conditions in which workload was systematically increased to an eventual patient-specific maximum. Methods A cohort study was conducted in which 18 individuals with chronic stroke underwent a maximal exertion cardiopulmonary exercise test on a stationary cycle ergometer, during which pedaling torque was continuously recorded. Measures of force production, pedaling symmetry, and pedaling smoothness were obtained. Results Mean Torque increased significantly (p < 0.05) for both legs from initial to terminal workloads. Mean torque Symmetry Index, calculated for down and upstroke portions of the pedaling action, improved from 0.37(0.29) to 0.29(0.35) during downstroke (p = 0.007), and worsened during the upstroke: -0.37(0.38) to -0.62(0.46) (p < 0.001) from initial to terminal workloads. Low Torque Duration improved from initial to terminal workloads, decreasing from 121.1(52.9) to 58.1(39.6) degrees (p < 0.001), respectively. Smoothness of pedaling improved significantly from initial to terminal workloads (p < 0.001). Conclusions Improved pedaling kinematics at terminal workloads indicate that individuals with stroke demonstrate improved motor control with respect to the timing, sequencing, and activation of hemiparetic lower extremity musculature compared to lower workloads. Therapeutic prescription involving higher resistance may be necessary to sufficiently engage and activate the paretic lower extremity.

  6. Student Workload and Assessment: Strategies to Manage Expectations and Inform Curriculum Development

    ERIC Educational Resources Information Center

    Scully, Glennda; Kerr, Rosemary

    2014-01-01

    This study reports the results of a survey of student study times and perceptions of workload in undergraduate and graduate accounting courses at a large Australian public university. The study was in response to student feedback expressing concerns about workload in courses. The presage factors of student workload and assessment in Biggs' 3P…

  7. Workload and non-contact injury incidence in elite football players competing in European leagues.

    PubMed

    Delecroix, Barthelemy; McCall, Alan; Dawson, Brian; Berthoin, Serge; Dupont, Gregory

    2018-06-02

    The aim of this study was to analyse the relationship between absolute and acute:chronic workload ratios and non-contact injury incidence in professional football players and to assess their predictive ability. Elite football players (n = 130) from five teams competing in European domestic and confederation level competitions were followed during one full competitive season. Non-contact injuries were recorded and using session rate of perceived exertion (s-RPE) internal absolute workload and acute:chronic (A:C) workload ratios (4-weeks, 3-weeks, 2-weeks and week-to-week) were calculated using a rolling days method. The relative risk (RR) of non-contact injury was increased (RR = 1.59, CI95%: 1.18-2.15) when a cumulative 4-week absolute workload was greater than 10629 arbitrary units (AU) in comparison with a workload between 3745 and 10628 AU. When the 3-week absolute workload was more than 8319 AU versus between 2822 and 8318 AU injury risk was also increased (RR= 1.46, CI95% 1.08-1.98). Injury incidence was higher when the 4-week A:C ratio was <0.85 versus >0.85 (RR = 1.31, CI95%: 1.02-1.70) and with a 3-week A:C ratio >1.30 versus <1.30 (RR = 1.37, CI95%: 1.05-1.77). Importantly, none of the A:C workload combinations showed high sensitivity or specificity. In elite European footballers, using internal workload (sRPE) revealed that cumulative workloads over 3 and 4 weeks were associated with injury incidence. Additionally, A:C workloads, using combinations of 2, 3 and 4 weeks as the C workloads were also associated with increased injury risk. No A:C workload combination was appropriate to predict injury.

  8. Cognitive Workload and Psychophysiological Parameters During Multitask Activity in Helicopter Pilots.

    PubMed

    Gaetan, Sophie; Dousset, Erick; Marqueste, Tanguy; Bringoux, Lionel; Bourdin, Christophe; Vercher, Jean-Louis; Besson, Patricia

    2015-12-01

    Helicopter pilots are involved in a complex multitask activity, implying overuse of cognitive resources, which may result in piloting task impairment or in decision-making failure. Studies usually investigate this phenomenon in well-controlled, poorly ecological situations by focusing on the correlation between physiological values and either cognitive workload or emotional state. This study aimed at jointly exploring workload induced by a realistic simulated helicopter flight mission and emotional state, as well as physiological markers. The experiment took place in the helicopter full flight dynamic simulator. Six participants had to fly on two missions. Workload level, skin conductance, RMS-EMG, and emotional state were assessed. Joint analysis of psychological and physiological parameters associated with workload estimation revealed particular dynamics in each of three profiles. 1) Expert pilots showed a slight increase of measured physiological parameters associated with the increase in difficulty level. Workload estimates never reached the highest level and the emotional state for this profile only referred to positive emotions with low emotional intensity. 2) Non-Expert pilots showed increasing physiological values as the perceived workload increased. However, their emotional state referred to either positive or negative emotions, with a greater variability in emotional intensity. 3) Intermediate pilots were similar to Expert pilots regarding emotional states and similar to Non-Expert pilots regarding physiological patterns. Overall, high interindividual variability of these results highlight the complex link between physiological and psychological parameters with workload, and question whether physiology alone could predict a pilot's inability to make the right decision at the right time.

  9. Operating room clinicians' ratings of workload: a vignette simulation study.

    PubMed

    Wallston, Kenneth A; Slagle, Jason M; Speroff, Ted; Nwosu, Sam; Crimin, Kimberly; Feurer, Irene D; Boettcher, Brent; Weinger, Matthew B

    2014-06-01

    Increased clinician workload is associated with medical errors and patient harm. The Quality and Workload Assessment Tool (QWAT) measures anticipated (pre-case) and perceived (post-case) clinical workload during actual surgical procedures using ratings of individual and team case difficulty from every operating room (OR) team member. The purpose of this study was to examine the QWAT ratings of OR clinicians who were not present in the OR but who read vignettes compiled from actual case documentation to assess interrater reliability and agreement with ratings made by clinicians involved in the actual cases. Thirty-six OR clinicians (13 anesthesia providers, 11 surgeons, and 12 nurses) used the QWAT to rate 6 cases varying from easy to moderately difficult based on actual ratings made by clinicians involved with the cases. Cases were presented and rated in random order. Before rating anticipated individual and team difficulty, the raters read prepared clinical vignettes containing case synopses and much of the same written case information that was available to the actual clinicians before the onset of each case. Then, before rating perceived individual and team difficulty, they read part 2 of the vignette consisting of detailed role-specific intraoperative data regarding the anesthetic and surgical course, unusual events, and other relevant contextual factors. Surgeons had higher interrater reliability on the QWAT than did OR nurses or anesthesia providers. For the anticipated individual and team workload ratings, there were no statistically significant differences between the actual ratings and the ratings obtained from the vignettes. There were differences for the 3 provider types in perceived individual workload for the median difficulty cases and in the perceived team workload for the median and more difficult cases. The case difficulty items on the QWAT seem to be sufficiently reliable and valid to be used in other studies of anticipated and perceived clinical

  10. Eye Tracking Metrics for Workload Estimation in Flight Deck Operation

    NASA Technical Reports Server (NTRS)

    Ellis, Kyle; Schnell, Thomas

    2010-01-01

    Flight decks of the future are being enhanced through improved avionics that adapt to both aircraft and operator state. Eye tracking allows for non-invasive analysis of pilot eye movements, from which a set of metrics can be derived to effectively and reliably characterize workload. This research identifies eye tracking metrics that correlate to aircraft automation conditions, and identifies the correlation of pilot workload to the same automation conditions. Saccade length was used as an indirect index of pilot workload: Pilots in the fully automated condition were observed to have on average, larger saccadic movements in contrast to the guidance and manual flight conditions. The data set itself also provides a general model of human eye movement behavior and so ostensibly visual attention distribution in the cockpit for approach to land tasks with various levels of automation, by means of the same metrics used for workload algorithm development.

  11. Interactive Query Processing in Big Data Systems: A Cross Industry Study of MapReduce Workloads

    DTIC Science & Technology

    2012-04-02

    invite cluster operators and the broader data management commu- nity to share additional knowledge about their MapReduce workloads. 9. ACKNOWLEDGMENTS...against real- life production MapReduce workloads. Knowledge of such workloads is currently limited to a handful of technology companies [19, 8, 48, 41...database management insights would benefit from checking workload assumptions against empirical measurements. The broad spectrum of workloads analyzed allows

  12. The Tla protein of Porphyromonas gingivalis W50: a homolog of the RI protease precursor (PrpRI) is an outer membrane receptor required for growth on low levels of hemin.

    PubMed

    Aduse-Opoku, J; Slaney, J M; Rangarajan, M; Muir, J; Young, K A; Curtis, M A

    1997-08-01

    The prpR1 gene of Porphyromonas gingivalis W50 encodes the polyprotein precursor (PrpRI) of an extracellular arginine-specific protease. PrpRI is organized into four distinct domains (pro, alpha, beta, and gamma) and is processed to a heterodimeric protease (RI) which comprises the alpha and beta components in a noncovalent association. The alpha component contains the protease active site, whereas the beta component appears to have a role in adherence and hemagglutination processes. DNA sequences homologous to the coding region for the RI beta component are present at multiple loci on the P. gingivalis chromosome and may represent a family of related genes. In this report, we describe the cloning, sequence analysis, and characterization of one of these homologous loci isolated in plasmid pJM7. The 6,041-bp P. gingivalis DNA fragment in pJM7 contains a major open reading frame of 3,291 bp with coding potential for a protein with an Mr 118,700. An internal region of the deduced sequence (V304 to N768) shows 98% identity to the beta domain of PrpRI, and the recombinant product of pJM7 is immunoreactive with an antibody specific to the RI beta component. The N terminus of the deduced sequence has regional similarity to TonB-linked receptors which are frequently involved in periplasmic translocation of hemin, iron, colicins, or vitamin B12 in other bacteria. We have therefore designated this gene tla (TonB-linked adhesin). In contrast to the parent strain, an isogenic mutant of P. gingivalis W50 in which the tla was insertionally inactivated was unable to grow in medium containing low concentrations of hemin (<2.5 mg liter(-1)), and hemin-depleted cells of this mutant failed to respond to hemin in an agar diffusion plate assay. These data suggest a role for this gene product in hemin acquisition and utilization. Furthermore, the mutant produced significantly less arginine- and lysine-specific protease activities than the parent strain, indicating that there may be a

  13. The Tla protein of Porphyromonas gingivalis W50: a homolog of the RI protease precursor (PrpRI) is an outer membrane receptor required for growth on low levels of hemin.

    PubMed Central

    Aduse-Opoku, J; Slaney, J M; Rangarajan, M; Muir, J; Young, K A; Curtis, M A

    1997-01-01

    The prpR1 gene of Porphyromonas gingivalis W50 encodes the polyprotein precursor (PrpRI) of an extracellular arginine-specific protease. PrpRI is organized into four distinct domains (pro, alpha, beta, and gamma) and is processed to a heterodimeric protease (RI) which comprises the alpha and beta components in a noncovalent association. The alpha component contains the protease active site, whereas the beta component appears to have a role in adherence and hemagglutination processes. DNA sequences homologous to the coding region for the RI beta component are present at multiple loci on the P. gingivalis chromosome and may represent a family of related genes. In this report, we describe the cloning, sequence analysis, and characterization of one of these homologous loci isolated in plasmid pJM7. The 6,041-bp P. gingivalis DNA fragment in pJM7 contains a major open reading frame of 3,291 bp with coding potential for a protein with an Mr 118,700. An internal region of the deduced sequence (V304 to N768) shows 98% identity to the beta domain of PrpRI, and the recombinant product of pJM7 is immunoreactive with an antibody specific to the RI beta component. The N terminus of the deduced sequence has regional similarity to TonB-linked receptors which are frequently involved in periplasmic translocation of hemin, iron, colicins, or vitamin B12 in other bacteria. We have therefore designated this gene tla (TonB-linked adhesin). In contrast to the parent strain, an isogenic mutant of P. gingivalis W50 in which the tla was insertionally inactivated was unable to grow in medium containing low concentrations of hemin (<2.5 mg liter(-1)), and hemin-depleted cells of this mutant failed to respond to hemin in an agar diffusion plate assay. These data suggest a role for this gene product in hemin acquisition and utilization. Furthermore, the mutant produced significantly less arginine- and lysine-specific protease activities than the parent strain, indicating that there may be a

  14. Urology residents experience comparable workload profiles when performing live porcine nephrectomies and robotic surgery virtual reality training modules.

    PubMed

    Mouraviev, Vladimir; Klein, Martina; Schommer, Eric; Thiel, David D; Samavedi, Srinivas; Kumar, Anup; Leveillee, Raymond J; Thomas, Raju; Pow-Sang, Julio M; Su, Li-Ming; Mui, Engy; Smith, Roger; Patel, Vipul

    2016-03-01

    In pursuit of improving the quality of residents' education, the Southeastern Section of the American Urological Association (SES AUA) hosts an annual robotic training course for its residents. The workshop involves performing a robotic live porcine nephrectomy as well as virtual reality robotic training modules. The aim of this study was to evaluate workload levels of urology residents when performing a live porcine nephrectomy and the virtual reality robotic surgery training modules employed during this workshop. Twenty-one residents from 14 SES AUA programs participated in 2015. On the first-day residents were taught with didactic lectures by faculty. On the second day, trainees were divided into two groups. Half were asked to perform training modules of the Mimic da Vinci-Trainer (MdVT, Mimic Technologies, Inc., Seattle, WA, USA) for 4 h, while the other half performed nephrectomy procedures on a live porcine model using the da Vinci Si robot (Intuitive Surgical Inc., Sunnyvale, CA, USA). After the first 4 h the groups changed places for another 4-h session. All trainees were asked to complete the NASA-TLX 1-page questionnaire following both the MdVT simulation and live animal model sessions. A significant interface and TLX interaction was observed. The interface by TLX interaction was further analyzed to determine whether the scores of each of the six TLX scales varied across the two interfaces. The means of the TLX scores observed at the two interfaces were similar. The only significant difference was observed for frustration, which was significantly higher at the simulation than the animal model, t (20) = 4.12, p = 0.001. This could be due to trainees' familiarity with live anatomical structures over skill set simulations which remain a real challenge to novice surgeons. Another reason might be that the simulator provides performance metrics for specific performance traits as well as composite scores for entire exercises. Novice trainees experienced

  15. Unsupervised classification of operator workload from brain signals.

    PubMed

    Schultze-Kraft, Matthias; Dähne, Sven; Gugler, Manfred; Curio, Gabriel; Blankertz, Benjamin

    2016-06-01

    In this study we aimed for the classification of operator workload as it is expected in many real-life workplace environments. We explored brain-signal based workload predictors that differ with respect to the level of label information required for training, including entirely unsupervised approaches. Subjects executed a task on a touch screen that required continuous effort of visual and motor processing with alternating difficulty. We first employed classical approaches for workload state classification that operate on the sensor space of EEG and compared those to the performance of three state-of-the-art spatial filtering methods: common spatial patterns (CSPs) analysis, which requires binary label information; source power co-modulation (SPoC) analysis, which uses the subjects' error rate as a target function; and canonical SPoC (cSPoC) analysis, which solely makes use of cross-frequency power correlations induced by different states of workload and thus represents an unsupervised approach. Finally, we investigated the effects of fusing brain signals and peripheral physiological measures (PPMs) and examined the added value for improving classification performance. Mean classification accuracies of 94%, 92% and 82% were achieved with CSP, SPoC, cSPoC, respectively. These methods outperformed the approaches that did not use spatial filtering and they extracted physiologically plausible components. The performance of the unsupervised cSPoC is significantly increased by augmenting it with PPM features. Our analyses ensured that the signal sources used for classification were of cortical origin and not contaminated with artifacts. Our findings show that workload states can be successfully differentiated from brain signals, even when less and less information from the experimental paradigm is used, thus paving the way for real-world applications in which label information may be noisy or entirely unavailable.

  16. Unsupervised classification of operator workload from brain signals

    NASA Astrophysics Data System (ADS)

    Schultze-Kraft, Matthias; Dähne, Sven; Gugler, Manfred; Curio, Gabriel; Blankertz, Benjamin

    2016-06-01

    Objective. In this study we aimed for the classification of operator workload as it is expected in many real-life workplace environments. We explored brain-signal based workload predictors that differ with respect to the level of label information required for training, including entirely unsupervised approaches. Approach. Subjects executed a task on a touch screen that required continuous effort of visual and motor processing with alternating difficulty. We first employed classical approaches for workload state classification that operate on the sensor space of EEG and compared those to the performance of three state-of-the-art spatial filtering methods: common spatial patterns (CSPs) analysis, which requires binary label information; source power co-modulation (SPoC) analysis, which uses the subjects’ error rate as a target function; and canonical SPoC (cSPoC) analysis, which solely makes use of cross-frequency power correlations induced by different states of workload and thus represents an unsupervised approach. Finally, we investigated the effects of fusing brain signals and peripheral physiological measures (PPMs) and examined the added value for improving classification performance. Main results. Mean classification accuracies of 94%, 92% and 82% were achieved with CSP, SPoC, cSPoC, respectively. These methods outperformed the approaches that did not use spatial filtering and they extracted physiologically plausible components. The performance of the unsupervised cSPoC is significantly increased by augmenting it with PPM features. Significance. Our analyses ensured that the signal sources used for classification were of cortical origin and not contaminated with artifacts. Our findings show that workload states can be successfully differentiated from brain signals, even when less and less information from the experimental paradigm is used, thus paving the way for real-world applications in which label information may be noisy or entirely unavailable.

  17. Homogeneous near surface activity distribution by double energy activation for TLA

    NASA Astrophysics Data System (ADS)

    Takács, S.; Ditrói, F.; Tárkányi, F.

    2007-10-01

    Thin layer activation (TLA) is a versatile tool for activating thin surface layers in order to study real-time the surface loss by wear, corrosion or erosion processes of the activated parts, without disassembling or stopping running mechanical structures or equipment. The research problem is the determination of the irradiation parameters to produce point-like or large area optimal activity-depth distribution in the sample. Different activity-depth profiles can be produced depending on the type of the investigated material and the nuclear reaction used. To produce activity that is independent of the depth up to a certain depth is desirable when the material removed from the surface by wear, corrosion or erosion can be collected completely. By applying dual energy irradiation the thickness of this quasi-constant activity layer can be increased or the deviation of the activity distribution from a constant value can be minimized. In the main, parts made of metals and alloys are suitable for direct activation, but by using secondary particle implantation the wear of other materials can also be studied in a surface range a few micrometers thick. In most practical cases activation of a point-like spot (several mm2) is enough to monitor the wear, corrosion or erosion, but for special problems relatively large surfaces areas of complicated spatial geometry need to be activated uniformly. Two ways are available for fulfilling this task, (1) production of large area beam spot or scanning the beam over the surface in question from the accelerator side, or (2) a programmed 3D movement of the sample from the target side. Taking into account the large variability of tasks occurring in practice, the latter method was chosen as the routine solution in our cyclotron laboratory.

  18. Debriefing decreases mental workload in surgical crisis: A randomized controlled trial.

    PubMed

    Boet, Sylvain; Sharma, Bharat; Pigford, Ashlee-Ann; Hladkowicz, Emily; Rittenhouse, Neil; Grantcharov, Teodor

    2017-05-01

    Mental workload is the amount of mental effort involved in performing a particular task. Crisis situations may increase mental workload, which can subsequently negatively impact operative performance and patient safety. This study aims to measure the impact of learning through debriefing and a systematic approach to crisis on trainees' mental workload in a simulated surgical crisis. Twenty junior surgical residents participated in a high-fidelity, simulated, postoperative crisis in a surgical ward environment (pretest). Participants were randomized to either an instructor-led debriefing, including performance feedback (intervention; n = 10) or no debriefing (control; n = 10). Subjects then immediately managed a second simulated crisis (post-test). Mental workload was assessed in real time during the scenarios using a previously validated, wireless, vibrotactile device. Mental workload was represented by subject response times to the vibrations, which were recorded and analyzed using the Mann-Whitney U test. Participants in the debriefing arm had a significantly reduced median response time in milliseconds (post-test minus pretest -695, quartile range -2,136 to -297) compared to participants in the control arm (42, -1,191 to 763), (between-arm difference P = .049). Debriefing after simulated surgical crisis situations may improve performance by decreasing trainee's mental workload during a subsequent simulated surgical crisis. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Wiltech Component Cleaning and Refurbishment Facility CFC Elimination Plan at NASA Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Williamson, Steve; Aman, Bob; Aurigema, Andrew; Melendez, Orlando

    1999-01-01

    The Wiltech Component Cleaning & Refurbishment Facility (WT-CCRF) at NASA Kennedy Space Center performs precision cleaning on approximately 200,000 metallic and non metallic components every year. WT-CCRF has developed a CFC elimination plan consisting of aqueous cleaning and verification and an economical dual solvent strategy for alternative solvent solution. Aqueous Verification Methodologies were implemented two years ago on a variety of Ground Support Equipment (GSE) components and sampling equipment. Today, 50% of the current workload is verified using aqueous methods and 90% of the total workload is degreased aqueously using, Zonyl and Brulin surfactants in ultrasonic baths. An additional estimated 20% solvent savings could be achieved if the proposed expanded use of aqueous methods are approved. Aqueous cleaning has shown to be effective, environmentally friendly and economical (i.e.. cost of materials, equipment, facilities and labor).

  20. Workloads in Australian emergency departments a descriptive study.

    PubMed

    Lyneham, Joy; Cloughessy, Liz; Martin, Valmai

    2008-07-01

    This study aimed to identify the current workload of clinical nurses, managers and educators in Australian Emergency Departments according to the classification of the department Additionally the relationship of experienced to inexperienced clinical staff was examined. A descriptive research method utilising a survey distributed to 394 Australian Emergency departments with a 21% response rate. Nursing workloads were calculated and a ratio of nurse to patient was established. The ratios included nurse to patient, management and educators to clinical staff. Additionally the percentage of junior to senior clinical staff was also calculated. Across all categories of emergency departments the mean nurse:patient ratios were 1:15 (am shift), 1:7 (pm shift) and 1:4 (night shift). During this period an average of 17.1% of attendances were admitted to hospital. There were 27 staff members for each manager and 23.3 clinical staff for each educator. The percentage of junior staff rostered ranged from 10% to 38%. Emergency nurses cannot work under such pressure as it may compromise the care given to patients and consequently have a negative effect on the nurse personally. However, emergency nurses are dynamically adjusting to the workload. Such conditions as described in this study could give rise to burnout and attrition of experienced emergency nurses as they cannot resolve the conflict between workload and providing quality nursing care.

  1. A comprehensive prediction and evaluation method of pilot workload

    PubMed Central

    Feng, Chuanyan; Wanyan, Xiaoru; Yang, Kun; Zhuang, Damin; Wu, Xu

    2018-01-01

    BACKGROUND: The prediction and evaluation of pilot workload is a key problem in human factor airworthiness of cockpit. OBJECTIVE: A pilot traffic pattern task was designed in a flight simulation environment in order to carry out the pilot workload prediction and improve the evaluation method. METHODS: The prediction of typical flight subtasks and dynamic workloads (cruise, approach, and landing) were built up based on multiple resource theory, and a favorable validity was achieved by the correlation analysis verification between sensitive physiological data and the predicted value. RESULTS: Statistical analysis indicated that eye movement indices (fixation frequency, mean fixation time, saccade frequency, mean saccade time, and mean pupil diameter), Electrocardiogram indices (mean normal-to-normal interval and the ratio between low frequency and sum of low frequency and high frequency), and Electrodermal Activity indices (mean tonic and mean phasic) were all sensitive to typical workloads of subjects. CONCLUSION: A multinominal logistic regression model based on combination of physiological indices (fixation frequency, mean normal-to-normal interval, the ratio between low frequency and sum of low frequency and high frequency, and mean tonic) was constructed, and the discriminate accuracy was comparatively ideal with a rate of 84.85%. PMID:29710742

  2. A comprehensive prediction and evaluation method of pilot workload.

    PubMed

    Feng, Chuanyan; Wanyan, Xiaoru; Yang, Kun; Zhuang, Damin; Wu, Xu

    2018-01-01

    The prediction and evaluation of pilot workload is a key problem in human factor airworthiness of cockpit. A pilot traffic pattern task was designed in a flight simulation environment in order to carry out the pilot workload prediction and improve the evaluation method. The prediction of typical flight subtasks and dynamic workloads (cruise, approach, and landing) were built up based on multiple resource theory, and a favorable validity was achieved by the correlation analysis verification between sensitive physiological data and the predicted value. Statistical analysis indicated that eye movement indices (fixation frequency, mean fixation time, saccade frequency, mean saccade time, and mean pupil diameter), Electrocardiogram indices (mean normal-to-normal interval and the ratio between low frequency and sum of low frequency and high frequency), and Electrodermal Activity indices (mean tonic and mean phasic) were all sensitive to typical workloads of subjects. A multinominal logistic regression model based on combination of physiological indices (fixation frequency, mean normal-to-normal interval, the ratio between low frequency and sum of low frequency and high frequency, and mean tonic) was constructed, and the discriminate accuracy was comparatively ideal with a rate of 84.85%.

  3. Filter bank common spatial patterns in mental workload estimation.

    PubMed

    Arvaneh, Mahnaz; Umilta, Alberto; Robertson, Ian H

    2015-01-01

    EEG-based workload estimation technology provides a real time means of assessing mental workload. Such technology can effectively enhance the performance of the human-machine interaction and the learning process. When designing workload estimation algorithms, a crucial signal processing component is the feature extraction step. Despite several studies on this field, the spatial properties of the EEG signals were mostly neglected. Since EEG inherently has a poor spacial resolution, features extracted individually from each EEG channel may not be sufficiently efficient. This problem becomes more pronounced when we use low-cost but convenient EEG sensors with limited stability which is the case in practical scenarios. To address this issue, in this paper, we introduce a filter bank common spatial patterns algorithm combined with a feature selection method to extract spatio-spectral features discriminating different mental workload levels. To evaluate the proposed algorithm, we carry out a comparative analysis between two representative types of working memory tasks using data recorded from an Emotiv EPOC headset which is a mobile low-cost EEG recording device. The experimental results showed that the proposed spatial filtering algorithm outperformed the state-of-the algorithms in terms of the classification accuracy.

  4. Proceedings of the First NASA Formal Methods Symposium

    NASA Technical Reports Server (NTRS)

    Denney, Ewen (Editor); Giannakopoulou, Dimitra (Editor); Pasareanu, Corina S. (Editor)

    2009-01-01

    Topics covered include: Model Checking - My 27-Year Quest to Overcome the State Explosion Problem; Applying Formal Methods to NASA Projects: Transition from Research to Practice; TLA+: Whence, Wherefore, and Whither; Formal Methods Applications in Air Transportation; Theorem Proving in Intel Hardware Design; Building a Formal Model of a Human-Interactive System: Insights into the Integration of Formal Methods and Human Factors Engineering; Model Checking for Autonomic Systems Specified with ASSL; A Game-Theoretic Approach to Branching Time Abstract-Check-Refine Process; Software Model Checking Without Source Code; Generalized Abstract Symbolic Summaries; A Comparative Study of Randomized Constraint Solvers for Random-Symbolic Testing; Component-Oriented Behavior Extraction for Autonomic System Design; Automated Verification of Design Patterns with LePUS3; A Module Language for Typing by Contracts; From Goal-Oriented Requirements to Event-B Specifications; Introduction of Virtualization Technology to Multi-Process Model Checking; Comparing Techniques for Certified Static Analysis; Towards a Framework for Generating Tests to Satisfy Complex Code Coverage in Java Pathfinder; jFuzz: A Concolic Whitebox Fuzzer for Java; Machine-Checkable Timed CSP; Stochastic Formal Correctness of Numerical Algorithms; Deductive Verification of Cryptographic Software; Coloured Petri Net Refinement Specification and Correctness Proof with Coq; Modeling Guidelines for Code Generation in the Railway Signaling Context; Tactical Synthesis Of Efficient Global Search Algorithms; Towards Co-Engineering Communicating Autonomous Cyber-Physical Systems; and Formal Methods for Automated Diagnosis of Autosub 6000.

  5. Designing workload analysis questionnaire to evaluate needs of employees

    NASA Astrophysics Data System (ADS)

    Astuti, Rahmaniyah Dwi; Navi, Muhammad Abdu Haq

    2018-02-01

    Incompatibility between workload with work capacity is one of main problem to make optimal result. In case at the office, there are constraints to determine workload because of non-repetitive works. Employees do work based on the targets set in a working period. At the end of the period is usually performed an evaluation of employees performance to evaluate needs of employees. The aims of this study to design a workload questionnaire tools to evaluate the efficiency level of position as indicator to determine needs of employees based on the Indonesian State Employment Agency Regulation on workload analysis. This research is applied to State-Owned Enterprise PT. X by determining 3 positions as a pilot project. Position A is held by 2 employees, position B is held by 7 employees, and position C is held by 6 employees. From the calculation result, position A has an efficiency level of 1,33 or "very good", position B has an efficiency level of 1.71 or "enough", and position C has an efficiency level of 1.03 or "very good". The application of this tools giving suggestion the needs of employees of position A is 3 people, position B is 5 people, and position C is 6 people. The difference between the number of employees and the calculation result is then analyzed by interviewing the employees to get more data about personal perception. It can be concluded that this workload evaluation tools can be used as an alternative solution to evaluate needs of employees in office.

  6. Investigating Facial Electromyography as an Indicator of Cognitive Workload

    DTIC Science & Technology

    2017-02-22

    Investigating Facial Electromyography as an Indicator of Cognitive Workload 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...Symposium on Aviation Psychology (ISAP) 9 – 11 May 2017 14. ABSTRACT Facial electromyography (fEMG) is an electromyographic measurement technique... cognitive workload. In the current study, two task-irrelevant facial muscles, corrugator supercilli and lateral frontalis, were monitored in real- time to

  7. Nursing workload in intensive care unit trauma patients: analysis of associated factors.

    PubMed

    Nogueira, Lilia de Souza; Domingues, Cristiane de Alencar; Poggetti, Renato Sérgio; de Sousa, Regina Marcia Cardoso

    2014-01-01

    From the perspective of nurses, trauma patients in the Intensive Care Unit (ICU) demand a high degree of nursing workload due to hemodynamic instability and the severity of trauma injuries. This study aims to identify the factors related to the high nursing workload required for trauma victims admitted to the ICU. This is a prospective, cross-sectional study using descriptive and correlation analyses, conducted with 200 trauma patients admitted to an ICU in the city of São Paulo, Brazil. The nursing workload was measured using the Nursing Activities Score (NAS). The distribution of the NAS values into tertiles led to the identification of two research groups: medium/low workload and high workload. The Chi-square, Fisher's exact, Mann-Whitney and multiple logistic regression tests were utilized for the analyses. The majority of patients were male (82.0%) and suffered blunt trauma (94.5%), with traffic accidents (57.5%) and falls (31.0%) being prevalent. The mean age was 40.7 years (± 18.6) and the mean NAS was 71.3% (± 16.9). Patient gender, the presence of pulmonary failure, the number of injured body regions and the risk of death according to the Simplified Acute Physiology Score II were factors associated with a high degree of nursing workload in the first 24 hours following admission to the ICU. Workload demand was higher in male patients with physiological instability and multiple severe trauma injuries who developed pulmonary failure.

  8. Work hours, workload, sleep and fatigue in Australian Rail Industry employees.

    PubMed

    Dorrian, Jillian; Baulk, Stuart D; Dawson, Drew

    2011-01-01

    Research suggests that less than 5 h sleep in the 24 h prior to work and/or more than 16 h of wakefulness can significantly increase the likelihood of fatigue-related impairment and error at work. Studies have also shown exponential safety declines with time on shift, with roughly double the likelihood of accident or injury after 10 h relative to the first 8h. While it is acknowledged that reduced sleep, increased wakefulness and longer work hours produce work-related fatigue, few studies have examined the impact of workload on this relationship. Studies in the rail industry have focused on drivers. This study investigated fatigue in a large sample of Australian Rail Industry Employees. Participants were from four companies (n = 90: 85m, 5f; mean age 40.2 ± 8.6 y). Data was analysed for a total of 713 shifts. Subjects wore wrist actigraphs and completed sleep and work diaries for 14-days. They also completed the Samn-Perelli Fatigue Scale at the beginning and end of shifts, and the NASA-TLX workload scale at least twice during each shift. Average (±SD) sleep length (7.2 ± 2.6h), prior wake at shift end (12.0 ± 4.7h), shift duration (8.0 ± 1.3) and fatigue (4.1 ± 1.3, "a little tired, less than fresh") were within limits generally considered acceptable from a fatigue perspective. However, participants received 5 h or less sleep in the prior 24 h on 13%, were awake for at least 16 h at the end of 16% and worked at least 10 h on 7% of shifts. Subjects reported that they felt "extremely tired, very difficult to concentrate," or "completely exhausted, unable to function effectively" on 13% of shifts. Sleep length (OR = 0.88, p < 0.01), shift duration (OR = 1.18, p < 0.05), night shift (REF = morning shift, OR = 2.12, p < 0.05) and workload ratings (OR = 1.2, p < 0.05) were significant predictors of ratings of extreme tiredness/exhaustion (yes/no). While on average, sleep loss, extended wakefulness, longer work hours and work-related fatigue do not appear

  9. Toward an Operational Definition of Workload: A Workload Assessment of Aviation Maneuvers

    DTIC Science & Technology

    2010-08-01

    and evaluated by the learner . With practice, the learner moves into the second phase, where optimal strategies are strengthened. The final stage of...The first phase demands a great amount of resources as performance is slow and prone to errors. During this phase, strategies are being formulated...asked to assess mental, physical, visual, aural , and verbal demands of each task. The new assessment is a cost effective method of assessing workload

  10. Nursing Workload and the Changing Health Care Environment: A Review of the Literature

    ERIC Educational Resources Information Center

    Neill, Denise

    2011-01-01

    Changes in the health care environment have impacted nursing workload, quality of care, and patient safety. Traditional nursing workload measures do not guarantee efficiency, nor do they adequately capture the complexity of nursing workload. Review of the literature indicates nurses perceive the quality of their work has diminished. Research has…

  11. Understanding the effect of workload on automation use for younger and older adults.

    PubMed

    McBride, Sara E; Rogers, Wendy A; Fisk, Arthur D

    2011-12-01

    This study examined how individuals, younger and older, interacted with an imperfect automated system. The impact of workload on performance and automation use was also investigated. Automation is used in situations characterized by varying levels of workload. As automated systems spread to domains such as transportation and the home, a diverse population of users will interact with automation. Research is needed to understand how different segments of the population use automation. Workload was systematically manipulated to create three levels (low, moderate, high) in a dual-task scenario in which participants interacted with a 70% reliable automated aid. Two experiments were conducted to assess automation use for younger and older adults. Both younger and older adults relied on the automation more than they complied with it. Among younger adults, high workload led to poorer performance and higher compliance, even when that compliance was detrimental. Older adults' performance was negatively affected by workload, but their compliance and reliance were unaffected. Younger and older adults were both able to use and double-check an imperfect automated system. Workload affected how younger adults complied with automation, particularly with regard to detecting automation false alarms. Older adults tended to comply and rely at fairly high rates overall, and this did not change with increased workload. Training programs for imperfect automated systems should vary workload and provide feedback about error types, and strategies for identifying errors. The ability to identify automation errors varies across individuals, thereby necessitating training.

  12. Air Traffic Management Research at NASA Ames Research Center

    NASA Technical Reports Server (NTRS)

    Lee, Katharine

    2005-01-01

    Since the late 1980's, NASA Ames researchers have been investigating ways to improve the air transportation system through the development of decision support automation. These software advances, such as the Center-TRACON Automation System (eTAS) have been developed with teams of engineers, software developers, human factors experts, and air traffic controllers; some ASA Ames decision support tools are currently operational in Federal Aviation Administration (FAA) facilities and some are in use by the airlines. These tools have provided air traffic controllers and traffic managers the capabilities to help reduce overall delays and holding, and provide significant cost savings to the airlines as well as more manageable workload levels for air traffic service providers. NASA is continuing to collaborate with the FAA, as well as other government agencies, to plan and develop the next generation of decision support tools that will support anticipated changes in the air transportation system, including a projected increase to three times today's air-traffic levels by 2025. The presentation will review some of NASA Ames' recent achievements in air traffic management research, and discuss future tool developments and concepts currently under consideration.

  13. Faculty Workload Studies: Perspectives, Needs, and Future Directions. ERIC Digest.

    ERIC Educational Resources Information Center

    Meyer, Katrina A.

    This digest reviews the literature and discusses issues concerning college faculty workload. Trends in the United States which have created interest in faculty workload issues are identified including faltering state economies in the late 1980s and rising costs of higher education especially of personnel. Criticism of higher education by the…

  14. Workload of the VTS Sector Operator And Implications for Task Design

    DOT National Transportation Integrated Search

    1994-12-01

    This study identifies the factors determining the VTS sector operator's workload and recommends : the most appropriate use of automation to manage that workload. Investigations were conducted at : VTS New York (Governors Island) and at VTS Puget Soun...

  15. The acute:chonic workload ratio in relation to injury risk in professional soccer.

    PubMed

    Malone, Shane; Owen, Adam; Newton, Matt; Mendes, Bruno; Collins, Kieran D; Gabbett, Tim J

    2017-06-01

    To examine the association between combined sRPE measures and injury risk in elite professional soccer. Observational cohort study. Forty-eight professional soccer players (mean±SD age of 25.3±3.1 yr) from two elite European teams were involved within a one season study. Players completed a test of intermittent-aerobic capacity (Yo-YoIR1) to assess player's injury risk in relation to intermittent aerobic capacity. Weekly workload measures and time loss injuries were recorded during the entire period. Rolling weekly sums and week-to-week changes in workload were measured, allowing for the calculation of the acute:chronic workload ratio, which was calculated by dividing the acute (1-weekly) and chronic (4-weekly) workloads. All derived workload measures were modelled against injury data using logistic regression. Odds ratios (OR) were reported against a reference group. Players who exerted pre-season 1-weekly loads of ≥1500 to ≤2120AU were at significantly higher risk of injury compared to the reference group of ≤1500AU (OR=1.95, p=0.006). Players with increased intermittent-aerobic capacity were better able to tolerate increased 1-weekly absolute changes in training load than players with lower fitness levels (OR=4.52, p=0.011). Players who exerted in-season acute:chronic workload ratios of >1.00 to <1.25 (OR=0.68, p=0.006) were at significantly lower risk of injury compared to the reference group (≤0.85). These findings demonstrate that an acute:chronic workload of between 1.00 and 1.25 is protective for professional soccer players. A higher intermittent-aerobic capacity appears to offer greater injury protection when players are exposed to rapid changes in workload in elite soccer players. Moderate workloads, coupled with moderate-low to moderate-high acute:chronic workload ratios, appear to be protective for professional soccer players. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  16. The effects of acceleration stress on human workload and manual control

    NASA Technical Reports Server (NTRS)

    Gill, R. T.; Albery, W. B.; Ward, S. L.

    1986-01-01

    The effects of +Gz stress on operator task performance and workload were assessed. Subjects were presented a two dimensional maze and were required to solve it as rapidly as possible (by moving a light dot through it via a trim switch on a control stick) while under G-stress at levels from +1 Gz to +6 Gz. The G-stress was provided by a human centrifuge. The effects of this stress were assessed by two techniques; (1) objective performance measures on the primary maze-solving task, and (2) subjective workload measures obtained using the subjective workload assessment technique (SWAT). It was found that while neither moderate (+3 Gz) nor high (+5 Gz and +6 Gz) levels of G-stress affected maze solving performance, the high G levels did increase significantly the subjective workload of the maze task.

  17. A human factors engineering conceptual framework of nursing workload and patient safety in intensive care units.

    PubMed

    Carayon, Pascale; Gürses, Ayşe P

    2005-10-01

    In this paper, we review the literature on nursing workload in intensive care units (ICUs) and its impact on patient safety and quality of working life of nurses. We then propose a conceptual framework of ICU nursing workload that defines causes, consequences and outcomes of workload. We identified four levels of nursing workload (ICU/unit level, job level, patient level, and situation level), and discuss measures associated with each of the four levels. A micro-level approach to ICU nursing workload at the situation level is proposed and recommended in order to reduce workload and mitigate its negative impact. Performance obstacles are conceptualized as causes of ICU nursing workload at the situation level.

  18. Defining and measuring pilot mental workload

    NASA Technical Reports Server (NTRS)

    Kantowitz, Barry H.

    1988-01-01

    A theory is sought that is general enough to help the researcher deal with a wide range of situations involving pilot mental stress. A limited capacity theory of attention forms the basis for the theory. Mental workload is then defined as an intervening variable, similar to attention, that modulates or indexes the tuning between the demands of the environment and the capacity of the organism. Two methods for measuring pilot mental workload are endorsed: (1) objective measures based on secondary tasks; and (2) psychophysiological measures, which have not yet been perfected but which will become more useful as theoretical models are refined. Secondary-task research is illustrated by simulator studies in which flying performance has been shown not to be adversely affected by adding a complex choice-reaction secondary task.

  19. Design Insights for MapReduce from Diverse Production Workloads

    DTIC Science & Technology

    2012-01-25

    different industries [5]. Consequently, there is a need to develop systematic knowledge of MapRe- duce behavior at both established users within technol...relevant to MapReduce-like systems that combine data movements and computation. 5.2 Task granularity Many MapReduce workload management mechanisms make...ex- ecutes the jobs given, versus what the jobs actually are. MapReduce workload managers currently optimize exe- cution scheduling and placement

  20. ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE-EVENT SIMULATION

    DTIC Science & Technology

    2016-03-24

    ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...in the United States. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...UNLIMITED. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION Erich W

  1. Understanding the Effect of Workload on Automation Use for Younger and Older Adults

    PubMed Central

    McBride, Sara E.; Rogers, Wendy A.; Fisk, Arthur D.

    2018-01-01

    Objective This study examined how individuals, younger and older, interacted with an imperfect automated system. The impact of workload on performance and automation use was also investigated. Background Automation is used in situations characterized by varying levels of workload. As automated systems spread to domains such as transportation and the home, a diverse population of users will interact with automation. Research is needed to understand how different segments of the population use automation. Method Workload was systematically manipulated to create three levels (low, moderate, high) in a dual-task scenario in which participants interacted with a 70% reliable automated aid. Two experiments were conducted to assess automation use for younger and older adults. Results Both younger and older adults relied on the automation more than they complied with it. Among younger adults, high workload led to poorer performance and higher compliance, even when that compliance was detrimental. Older adults’ performance was negatively affected by workload, but their compliance and reliance were unaffected. Conclusion Younger and older adults were both able to use and double-check an imperfect automated system. Workload affected how younger adults complied with automation, particularly with regard to detecting automation false alarms. Older adults tended to comply and rely at fairly high rates overall, and this did not change with increased workload. Application Training programs for imperfect automated systems should vary workload and provide feedback about error types, and strategies for identifying errors. The ability to identify automation errors varies across individuals, thereby necessitating training. PMID:22235529

  2. Impact of Conflict Avoidance Responsibility Allocation on Pilot Workload in a Distributed Air Traffic Management System

    NASA Technical Reports Server (NTRS)

    Ligda, Sarah V.; Dao, Arik-Quang V.; Vu, Kim-Phuong; Strybel, Thomas Z.; Battiste, Vernol; Johnson, Walter W.

    2010-01-01

    Pilot workload was examined during simulated flights requiring flight deck-based merging and spacing while avoiding weather. Pilots used flight deck tools to avoid convective weather and space behind a lead aircraft during an arrival into Louisville International airport. Three conflict avoidance management concepts were studied: pilot, controller or automation primarily responsible. A modified Air Traffic Workload Input Technique (ATWIT) metric showed highest workload during the approach phase of flight and lowest during the en-route phase of flight (before deviating for weather). In general, the modified ATWIT was shown to be a valid and reliable workload measure, providing more detailed information than post-run subjective workload metrics. The trend across multiple workload metrics revealed lowest workload when pilots had both conflict alerting and responsibility of the three concepts, while all objective and subjective measures showed highest workload when pilots had no conflict alerting or responsibility. This suggests that pilot workload was not tied primarily to responsibility for resolving conflicts, but to gaining and/or maintaining situation awareness when conflict alerting is unavailable.

  3. Mental workload during n-back task-quantified in the prefrontal cortex using fNIRS.

    PubMed

    Herff, Christian; Heger, Dominic; Fortmann, Ole; Hennrich, Johannes; Putze, Felix; Schultz, Tanja

    2013-01-01

    When interacting with technical systems, users experience mental workload. Particularly in multitasking scenarios (e.g., interacting with the car navigation system while driving) it is desired to not distract the users from their primary task. For such purposes, human-machine interfaces (HCIs) are desirable which continuously monitor the users' workload and dynamically adapt the behavior of the interface to the measured workload. While memory tasks have been shown to elicit hemodynamic responses in the brain when averaging over multiple trials, a robust single trial classification is a crucial prerequisite for the purpose of dynamically adapting HCIs to the workload of its user. The prefrontal cortex (PFC) plays an important role in the processing of memory and the associated workload. In this study of 10 subjects, we used functional Near-Infrared Spectroscopy (fNIRS), a non-invasive imaging modality, to sample workload activity in the PFC. The results show up to 78% accuracy for single-trial discrimination of three levels of workload from each other. We use an n-back task (n ∈ {1, 2, 3}) to induce different levels of workload, forcing subjects to continuously remember the last one, two, or three of rapidly changing items. Our experimental results show that measuring hemodynamic responses in the PFC with fNIRS, can be used to robustly quantify and classify mental workload. Single trial analysis is still a young field that suffers from a general lack of standards. To increase comparability of fNIRS methods and results, the data corpus for this study is made available online.

  4. Mental workload during n-back task—quantified in the prefrontal cortex using fNIRS

    PubMed Central

    Herff, Christian; Heger, Dominic; Fortmann, Ole; Hennrich, Johannes; Putze, Felix; Schultz, Tanja

    2014-01-01

    When interacting with technical systems, users experience mental workload. Particularly in multitasking scenarios (e.g., interacting with the car navigation system while driving) it is desired to not distract the users from their primary task. For such purposes, human-machine interfaces (HCIs) are desirable which continuously monitor the users' workload and dynamically adapt the behavior of the interface to the measured workload. While memory tasks have been shown to elicit hemodynamic responses in the brain when averaging over multiple trials, a robust single trial classification is a crucial prerequisite for the purpose of dynamically adapting HCIs to the workload of its user. The prefrontal cortex (PFC) plays an important role in the processing of memory and the associated workload. In this study of 10 subjects, we used functional Near-Infrared Spectroscopy (fNIRS), a non-invasive imaging modality, to sample workload activity in the PFC. The results show up to 78% accuracy for single-trial discrimination of three levels of workload from each other. We use an n-back task (n ∈ {1, 2, 3}) to induce different levels of workload, forcing subjects to continuously remember the last one, two, or three of rapidly changing items. Our experimental results show that measuring hemodynamic responses in the PFC with fNIRS, can be used to robustly quantify and classify mental workload. Single trial analysis is still a young field that suffers from a general lack of standards. To increase comparability of fNIRS methods and results, the data corpus for this study is made available online. PMID:24474913

  5. A graphical weather system design for the NASA transport systems research vehicle B-737

    NASA Technical Reports Server (NTRS)

    Scanlon, Charles H.

    1992-01-01

    A graphical weather system was designed for testing in the NASA Transport Systems Research Vehicle B-737 airplane and simulator. The purpose of these tests was to measure the impact of graphical weather products on aircrew decision processes, weather situation awareness, reroute clearances, workload, and weather monitoring. The flight crew graphical weather interface is described along with integration of the weather system with the flight navigation system, and data link transmission methods for sending weather data to the airplane.

  6. Use of EEG workload indices for diagnostic monitoring of vigilance decrement.

    PubMed

    Kamzanova, Altyngul T; Kustubayeva, Almira M; Matthews, Gerald

    2014-09-01

    A study was run to test which of five electroencephalographic (EEG) indices was most diagnostic of loss of vigilance at two levels of workload. EEG indices of alertness include conventional spectral power measures as well as indices combining measures from multiple frequency bands, such as the Task Load Index (TLI) and the Engagement Index (El). However, it is unclear which indices are optimal for early detection of loss of vigilance. Ninety-two participants were assigned to one of two experimental conditions, cued (lower workload) and uncued (higher workload), and then performed a 40-min visual vigilance task. Performance on this task is believed to be limited by attentional resource availability. EEG was recorded continuously. Performance, subjective state, and workload were also assessed. The task showed a vigilance decrement in performance; cuing improved performance and reduced subjective workload. Lower-frequency alpha (8 to 10.9 Hz) and TLI were most sensitive to the task parameters. The magnitude of temporal change was larger for lower-frequency alpha. Surprisingly, higher TLI was associated with superior performance. Frontal theta and El were influenced by task workload only in the final period of work. Correlational data also suggested that the indices are distinct from one another. Lower-frequency alpha appears to be the optimal index for monitoring vigilance on the task used here, but further work is needed to test how diagnosticity of EEG indices varies with task demands. Lower-frequency alpha may be used to diagnose loss of operator alertness on tasks requiring vigilance.

  7. Scaling Deep Learning Workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gawande, Nitin A.; Landwehr, Joshua B.; Daily, Jeffrey A.

    Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors --- including NVIDIA, Intel, AMD and IBM --- have architectural road-maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. This paper provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path. Our evaluation consists of amore » cross section of convolutional neural net workloads: CifarNet, CaffeNet, AlexNet and GoogleNet topologies using the Cifar10 and ImageNet datasets. The workloads are vendor optimized for each architecture. GPUs provide the highest overall raw performance. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and KNL can be competitive when considering performance/watt. Furthermore, NVLink is critical to GPU scaling.« less

  8. Does daily nurse staffing match ward workload variability? Three hospitals' experiences.

    PubMed

    Gabbay, Uri; Bukchin, Michael

    2009-01-01

    Nurse shortage and rising healthcare resource burdens mean that appropriate workforce use is imperative. This paper aims to evaluate whether daily nursing staffing meets ward workload needs. Nurse attendance and daily nurses' workload capacity in three hospitals were evaluated. Statistical process control was used to evaluate intra-ward nurse workload capacity and day-to-day variations. Statistical process control is a statistics-based method for process monitoring that uses charts with predefined target measure and control limits. Standardization was performed for inter-ward analysis by converting ward-specific crude measures to ward-specific relative measures by dividing observed/expected. Two charts: acceptable and tolerable daily nurse workload intensity, were defined. Appropriate staffing indicators were defined as those exceeding predefined rates within acceptable and tolerable limits (50 percent and 80 percent respectively). A total of 42 percent of the overall days fell within acceptable control limits and 71 percent within tolerable control limits. Appropriate staffing indicators were met in only 33 percent of wards regarding acceptable nurse workload intensity and in only 45 percent of wards regarding tolerable workloads. The study work did not differentiate crude nurse attendance and it did not take into account patient severity since crude bed occupancy was used. Double statistical process control charts and certain staffing indicators were used, which is open to debate. Wards that met appropriate staffing indicators prove the method's feasibility. Wards that did not meet appropriate staffing indicators prove the importance and the need for process evaluations and monitoring. Methods presented for monitoring daily staffing appropriateness are simple to implement either for intra-ward day-to-day variation by using nurse workload capacity statistical process control charts or for inter-ward evaluation using standardized measure of nurse workload intensity

  9. The impact of draught related to air velocity, air temperature and workload.

    PubMed

    Griefahn, B; Künemund, C; Gehring, U

    2001-08-01

    This experimental study was designed to test the hypotheses that the effects of draught increase with higher air velocity, with lower air temperature, and with lower workload. Thirty healthy young males were exposed to horizontal draught during 55 min while they operated an arm ergometer in a standing posture. Air velocity, air temperature, and workload were varied in 3 steps each, between 11 and 23 degrees C, 0.1 and 0.3 m/s, and 104 to 156 W/m2, respectively. The 27 combinations were distributed over subjects in a fractional factorial 3(3)-design. The participants were clothed for thermal neutrality. Workload was measured at the end of the sessions by respirometry. Draught-induced annoyance was determined every 5 min, separately for 10 body sites. Corresponding skin temperature was also recorded. The hypotheses were verified for the influence of air velocity and air temperature. Regarding workload, local heat production is probably decisive, meaning that draft-induced local annoyance is inversely related to workload in active but independent from workload in non-active body areas. To improve the situation for the workers concerned it is suggested to apply protective gloves that cover an as great area of the forearms as possible and to limit airflows to mean velocities of less than 0.2 m/s (with turbulence intensities of 50%).

  10. The multitasking framework: the effects of increasing workload on acute psychobiological stress reactivity.

    PubMed

    Wetherell, Mark A; Carter, Kirsty

    2014-04-01

    A variety of techniques exist for eliciting acute psychological stress in the laboratory; however, they vary in terms of their ease of use, reliability to elicit consistent responses and the extent to which they represent the stressors encountered in everyday life. There is, therefore, a need to develop simple laboratory techniques that reliably elicit psychobiological stress reactivity that are representative of the types of stressors encountered in everyday life. The multitasking framework is a performance-based, cognitively demanding stressor, representative of environments where individuals are required to attend and respond to several different stimuli simultaneously with varying levels of workload. Psychological (mood and perceived workload) and physiological (heart rate and blood pressure) stress reactivity was observed in response to a 15-min period of multitasking at different levels of workload intensity in a sample of 20 healthy participants. Multitasking stress elicited increases in heart rate and blood pressure, and increased workload intensity elicited dose-response increases in levels of perceived workload and mood. As individuals rarely attend to single tasks in real life, the multitasking framework provides an alternative technique for modelling acute stress and workload in the laboratory. Copyright © 2013 John Wiley & Sons, Ltd.

  11. From trees to forest: relational complexity network and workload of air traffic controllers.

    PubMed

    Zhang, Jingyu; Yang, Jiazhong; Wu, Changxu

    2015-01-01

    In this paper, we propose a relational complexity (RC) network framework based on RC metric and network theory to model controllers' workload in conflict detection and resolution. We suggest that, at the sector level, air traffic showing a centralised network pattern can provide cognitive benefits in visual search and resolution decision which will in turn result in lower workload. We found that the network centralisation index can account for more variance in predicting perceived workload and task completion time in both a static conflict detection task (Study 1) and a dynamic one (Study 2) in addition to other aircraft-level and pair-level factors. This finding suggests that linear combination of aircraft-level or dyad-level information may not be adequate and the global-pattern-based index is necessary. Theoretical and practical implications of using this framework to improve future workload modelling and management are discussed. We propose a RC network framework to model the workload of air traffic controllers. The effect of network centralisation was examined in both a static conflict detection task and a dynamic one. Network centralisation was predictive of perceived workload and task completion time over and above other control variables.

  12. Classification of driving workload affected by highway alignment conditions based on classification and regression tree algorithm.

    PubMed

    Hu, Jiangbi; Wang, Ronghua

    2018-02-17

    Guaranteeing a safe and comfortable driving workload can contribute to reducing traffic injuries. In order to provide safe and comfortable threshold values, this study attempted to classify driving workload from the aspects of human factors mainly affected by highway geometric conditions and to determine the thresholds of different workload classifications. This article stated a hypothesis that the values of driver workload change within a certain range. Driving workload scales were stated based on a comprehensive literature review. Through comparative analysis of different psychophysiological measures, heart rate variability (HRV) was chosen as the representative measure for quantifying driving workload by field experiments. Seventy-two participants (36 car drivers and 36 large truck drivers) and 6 highways with different geometric designs were selected to conduct field experiments. A wearable wireless dynamic multiparameter physiological detector (KF-2) was employed to detect physiological data that were simultaneously correlated to the speed changes recorded by a Global Positioning System (GPS) (testing time, driving speeds, running track, and distance). Through performing statistical analyses, including the distribution of HRV during the flat, straight segments and P-P plots of modified HRV, a driving workload calculation model was proposed. Integrating driving workload scales with values, the threshold of each scale of driving workload was determined by classification and regression tree (CART) algorithms. The driving workload calculation model was suitable for driving speeds in the range of 40 to 120 km/h. The experimental data of 72 participants revealed that driving workload had a significant effect on modified HRV, revealing a change in driving speed. When the driving speed was between 100 and 120 km/h, drivers showed an apparent increase in the corresponding modified HRV. The threshold value of the normal driving workload K was between -0.0011 and 0

  13. Impact of computerized information systems on workload in operating room and intensive care unit.

    PubMed

    Bosman, R J

    2009-03-01

    The number of operating rooms and intensive care departments equipped with a clinical information system (CIS) is rapidly expanding. Amongst the putative advantages of such an installation, reduction in workload for the clinician is one of the most appealing. The scarce studies looking at workload variations associated with the implementation of a CIS, only focus on direct workload discarding indirect changes in workload. Descriptions of the various methods to quantify workload are provided. The hypothesis that a third generation CIS can reduce documentation time for ICU nurses and increase time they spend on patient care, is supported by recent literature. Though it seems obvious to extrapolate these advantages of a CIS to the anesthesiology department or physicians in the intensive care, studies examining this assumption are scarce.

  14. CO2 Washout Testing of NASA Space Suits

    NASA Technical Reports Server (NTRS)

    Norcross, Jason

    2012-01-01

    During the presentation "CO2 Washout Testing of NASA Spacesuits," Jason Norcross discussed the results of recent carbon dioxide CO2 washout testing of NASA spacesuits including the Rear Entry I-suit (REI), Enhanced Mobility Advanced Crew Escape Suit (EM-ACES), and possibly the ACES and Z-1 EVA prototype. When a spacesuit is used during ground testing, adequate CO2 washout must be provided for the suited subject. Symptoms of acute CO2 exposure depend on the partial pressure of CO2 (ppCO2) available to enter the lungs during respiration. The primary factors during ground-based testing that influence the ppCO2 level in the oronasal area include the metabolic rate of the subject and air flow through the suit. These tests were done to characterize inspired oronasal ppCO2 for a range of workloads and flow rates for which ground testing is nominally performed. During this presentation, Norcross provided descriptions of the spacesuits, test hardware, methodology, and results, as well as implications for future ground testing and verification of flight requirements.

  15. Predicting the Consequences of Workload Management Strategies with Human Performance Modeling

    NASA Technical Reports Server (NTRS)

    Mitchell, Diane Kuhl; Samma, Charneta

    2011-01-01

    Human performance modelers at the US Army Research Laboratory have developed an approach for establishing Soldier high workload that can be used for analyses of proposed system designs. Their technique includes three key components. To implement the approach in an experiment, the researcher would create two experimental conditions: a baseline and a design alternative. Next they would identify a scenario in which the test participants perform all their representative concurrent interactions with the system. This scenario should include any events that would trigger a different set of goals for the human operators. They would collect workload values during both the control and alternative design condition to see if the alternative increased workload and decreased performance. They have successfully implemented this approach for military vehicle. designs using the human performance modeling tool, IMPRINT. Although ARL researches use IMPRINT to implement their approach, it can be applied to any workload analysis. Researchers using other modeling and simulations tools or conducting experiments or field tests can use the same approach.

  16. Psychological Detachment Mediating the Daily Relationship between Workload and Marital Satisfaction

    PubMed Central

    Germeys, Lynn; De Gieter, Sara

    2017-01-01

    Scholars already demonstrated that psychologically detaching from work after workhours can diminish or avoid the negative effects of job demands on employees' well-being. In this study, we examined a curvilinear relationship between workload and psychological detachment. Moreover, we investigated the moderating influence of an employee's work-home segmentation preference on the relation between detachment and marital satisfaction. In addition, we applied and extended the stressor-detachment model by examining detachment as a mediator of the relation between workload and marital satisfaction. A total of 136 employees participated in our daily diary survey study during 10 consecutive working days. The results of the Bayesian 2-level path analyses revealed a negative linear and curvilinear relationship between workload and psychological detachment on a daily basis. Daily detachment positively related to marital satisfaction, with one's preference to segment work from home reinforcing this relationship. Moreover, psychological detachment fully mediated the daily relationship between workload and marital satisfaction. Implications for practice and suggestions for future research are discussed. PMID:28101076

  17. The impact of automation on workload and dispensing errors in a hospital pharmacy.

    PubMed

    James, K Lynette; Barlow, Dave; Bithell, Anne; Hiom, Sarah; Lord, Sue; Pollard, Mike; Roberts, Dave; Way, Cheryl; Whittlesea, Cate

    2013-04-01

    To determine the effect of installing an original-pack automated dispensing system (ADS) on dispensary workload and prevented dispensing incidents in a hospital pharmacy. Data on dispensary workload and prevented dispensing incidents, defined as dispensing errors detected and reported before medication had left the pharmacy, were collected over 6 weeks at a National Health Service hospital in Wales before and after the installation of an ADS. Workload was measured by non-participant observation using the event recording technique. Prevented dispensing incidents were self-reported by pharmacy staff on standardised forms. Median workloads (measured as items dispensed/person/hour) were compared using Mann-Whitney U tests and rate of prevented dispensing incidents were compared using Chi-square test. Spearman's rank correlation was used to examine the association between workload and prevented dispensing incidents. A P value of ≤0.05 was considered statistically significant. Median dispensary workload was significantly lower pre-automation (9.20 items/person/h) compared to post-automation (13.17 items/person/h, P < 0.001). Rate of prevented dispensing incidents was significantly lower post-automation (0.28%) than pre-automation (0.64%, P < 0.0001) but there was no difference (P = 0.277) between the types of dispensing incidents. A positive association existed between workload and prevented dispensing incidents both pre- (ρ = 0.13, P = 0.015) and post-automation (ρ = 0.23, P < 0.001). Dispensing incidents were found to occur during prolonged periods of moderate workload or after a busy period. Study findings suggest that automation improves dispensing efficiency and reduces the rate of prevented dispensing incidents. It is proposed that prevented dispensing incidents frequently occurred during periods of high workload due to involuntary automaticity. Prevented dispensing incidents occurring after a busy period were attributed to staff

  18. Estimating cognitive workload using wavelet entropy-based features during an arithmetic task.

    PubMed

    Zarjam, Pega; Epps, Julien; Chen, Fang; Lovell, Nigel H

    2013-12-01

    Electroencephalography (EEG) has shown promise as an indicator of cognitive workload; however, precise workload estimation is an ongoing research challenge. In this investigation, seven levels of workload were induced using an arithmetic task, and the entropy of wavelet coefficients extracted from EEG signals is shown to distinguish all seven levels. For a subject-independent multi-channel classification scheme, the entropy features achieved high accuracy, up to 98% for channels from the frontal lobes, in the delta frequency band. This suggests that a smaller number of EEG channels in only one frequency band can be deployed for an effective EEG-based workload classification system. Together with analysis based on phase locking between channels, these results consistently suggest increased synchronization of neural responses for higher load levels. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Injury risk-workload associations in NCAA American college football.

    PubMed

    Sampson, J A; Murray, A; Williams, S; Halseth, T; Hanisch, J; Golden, G; Fullagar, H H K

    2018-05-22

    To determine injury risk-workload associations in collegiate American Football. Retrospective analysis. Workload and injury data was recorded from 52 players during a full NCAA football season. Acute, chronic, and a range of acute:chronic workload ratios (ACWR: 7:14, 7:21 and 7:28 day) calculated using rolling and exponentially weighted moving averages (EWMA) were plotted against non-contact injuries (regardless of time lost or not) sustained within 3- and 7-days. Injury risks were also determined relative to position and experience. 105 non-contact injuries (18 game- and 87 training-related) were observed with almost 40% sustained during the pre-season. 7-21 day EWMA ACWR's with a 3-day injury lag were most closely associated with injury (R 2 =0.54). Relative injury risks were >3× greater with high compared to moderate and low ratios and magnified when combined with low 21-day chronic workloads (injury probability=92.1%). Injury risks were similar across positions. 'Juniors' presented likely and possibly increased overall injury risk compared to 'Freshman' (RR: 1.94, CI 1.07-3.52) and 'Seniors' (RR: 1.7, CI 0.92-3.14), yet no specific ACWR - experience or - position interactions were identified. High injury rates during college football pre-season training may be associated with high acute loads. In-season injury risks were greatest with high ACWR and evident even when including (more common and less serious) non-time loss injuries. Substantially increased injury risks when low 21-day chronic workloads and concurrently high EWMA ACWR highlights the importance of load management for individuals with chronic game- (non-involved on game day) and or training (following injury) absences. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  20. Electronic Health Record Alert-Related Workload as a Predictor of Burnout in Primary Care Providers.

    PubMed

    Gregory, Megan E; Russo, Elise; Singh, Hardeep

    2017-07-05

    Electronic health records (EHRs) have been shown to increase physician workload. One EHR feature that contributes to increased workload is asynchronous alerts (also known as inbox notifications) related to test results, referral responses, medication refill requests, and messages from physicians and other health care professionals. This alert-related workload results in negative cognitive outcomes, but its effect on affective outcomes, such as burnout, has been understudied. To examine EHR alert-related workload (both objective and subjective) as a predictor of burnout in primary care providers (PCPs), in order to ultimately inform interventions aimed at reducing burnout due to alert workload. A cross-sectional questionnaire and focus group of 16 PCPs at a large medical center in the southern United States. Subjective, but not objective, alert workload was related to two of the three dimensions of burnout, including physical fatigue (p = 0.02) and cognitive weariness (p = 0.04), when controlling for organizational tenure. To reduce alert workload and subsequent burnout, participants indicated a desire to have protected time for alert management, fewer unnecessary alerts, and improvements to the EHR system. Burnout associated with alert workload may be in part due to subjective differences at an individual level, and not solely a function of the objective work environment. This suggests the need for both individual and organizational-level interventions to improve alert workload and subsequent burnout. Additional research should confirm these findings in larger, more representative samples.

  1. Cardiovascular responses to plyometric exercise are affected by workload in athletes

    PubMed Central

    Arazi, Hamid; Mahdavi, Seyed Amir; Nasiri, Seyed Omid Mirfalah

    2014-01-01

    Introduction With regard to blood pressure responses to plyometric exercise and decreasing blood pressure after exercise (post-exercise hypotension), the influence of different workloads of plyometric exercise on blood pressure is not clear. Aim The purpose of this investigation was to examine the effects of a low, moderate and high workload of plyometric exercise on the post-exercise systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR) and rate-pressure product (RPP) responses in athletes. Material and methods Ten male athletes (age: 22.6 ±0.5 years; height: 178.2 ±3.3 cm; and body mass: 75.2 ±2.8 kg) underwent PE protocols involving 5 × 10 reps (Low Workload – LW), 10 × 10 reps (Moderate Workload – MW), and 15 × 10 reps (High Workload – HW) depth jump exercise from a 50-cm box in 3 non-consecutive days. After each exercise session, SBP, DBP and HR were measured every 10 min for a period of 70 min. Results No significant differences were observed among post-exercise SBP and DBP when the protocols (LW, MW and HW) were compared. The MW and HW protocols showed greater increases in HR compared with LW. Also the HW indicated greater increases than LW in RPP at post-exercise (p < 0.05). Conclusions All protocols increased SBP, HR and RPP responses at the 10th and 20th min of post-exercise. With regard to different workloads of plyometric exercise, HW condition indicated greater increases in HR and RPP and strength and conditioning professionals and athletes must keep in their mind that HW of plyometric exercise induces greater cardiovascular responses. PMID:24799919

  2. Cardiovascular responses to plyometric exercise are affected by workload in athletes.

    PubMed

    Arazi, Hamid; Asadi, Abbas; Mahdavi, Seyed Amir; Nasiri, Seyed Omid Mirfalah

    2014-01-01

    With regard to blood pressure responses to plyometric exercise and decreasing blood pressure after exercise (post-exercise hypotension), the influence of different workloads of plyometric exercise on blood pressure is not clear. The purpose of this investigation was to examine the effects of a low, moderate and high workload of plyometric exercise on the post-exercise systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR) and rate-pressure product (RPP) responses in athletes. TEN MALE ATHLETES (AGE: 22.6 ±0.5 years; height: 178.2 ±3.3 cm; and body mass: 75.2 ±2.8 kg) underwent PE protocols involving 5 × 10 reps (Low Workload - LW), 10 × 10 reps (Moderate Workload - MW), and 15 × 10 reps (High Workload - HW) depth jump exercise from a 50-cm box in 3 non-consecutive days. After each exercise session, SBP, DBP and HR were measured every 10 min for a period of 70 min. No significant differences were observed among post-exercise SBP and DBP when the protocols (LW, MW and HW) were compared. The MW and HW protocols showed greater increases in HR compared with LW. Also the HW indicated greater increases than LW in RPP at post-exercise (p < 0.05). All protocols increased SBP, HR and RPP responses at the 10(th) and 20(th) min of post-exercise. With regard to different workloads of plyometric exercise, HW condition indicated greater increases in HR and RPP and strength and conditioning professionals and athletes must keep in their mind that HW of plyometric exercise induces greater cardiovascular responses.

  3. Complexity and Pilot Workload Metrics for the Evaluation of Adaptive Flight Controls on a Full Scale Piloted Aircraft

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Schaefer, Jacob; Burken, John J.; Larson, David; Johnson, Marcus

    2014-01-01

    Flight research has shown the effectiveness of adaptive flight controls for improving aircraft safety and performance in the presence of uncertainties. The National Aeronautics and Space Administration's (NASA)'s Integrated Resilient Aircraft Control (IRAC) project designed and conducted a series of flight experiments to study the impact of variations in adaptive controller design complexity on performance and handling qualities. A novel complexity metric was devised to compare the degrees of simplicity achieved in three variations of a model reference adaptive controller (MRAC) for NASA's F-18 (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) Full-Scale Advanced Systems Testbed (Gen-2A) aircraft. The complexity measures of these controllers are also compared to that of an earlier MRAC design for NASA's Intelligent Flight Control System (IFCS) project and flown on a highly modified F-15 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois). Pilot comments during the IRAC research flights pointed to the importance of workload on handling qualities ratings for failure and damage scenarios. Modifications to existing pilot aggressiveness and duty cycle metrics are presented and applied to the IRAC controllers. Finally, while adaptive controllers may alleviate the effects of failures or damage on an aircraft's handling qualities, they also have the potential to introduce annoying changes to the flight dynamics or to the operation of aircraft systems. A nuisance rating scale is presented for the categorization of nuisance side-effects of adaptive controllers.

  4. "Operation Workload" : a study of passenger energy expenditure during an emergency evacuation.

    DOT National Transportation Integrated Search

    1989-03-01

    In an earlier study at the Civil Aeromedical Institute, workloads were determined for passengers during an emergency evacuation. The evacuation tests were conducted in an orderly manner and were suggested as representative of a moderate workload. The...

  5. Panel workload assessment in US primary care: accounting for non-face-to-face panel management activities.

    PubMed

    Arndt, Brian; Tuan, Wen-Jan; White, Jennifer; Schumacher, Jessica

    2014-01-01

    An understanding of primary care provider (PCP) workload is an important consideration in establishing optimal PCP panel size. However, no widely acceptable measure of PCP workload exists that incorporates the effort involved with both non-face-to-face patient care activities and face-to-face encounters. Accounting for this gap is critical given the increase in non-face-to-face PCP activities that has accompanied electronic health records (EHRs) (eg, electronic messaging). Our goal was to provide a comprehensive assessment of perceived PCP workload, accounting for aspects of both face-to-face and non-face-to-face encounters. Internal medicine, family medicine, and pediatric PCPs completed a self-administered survey about the perceived workload involved with face-to-face and non-face-to-face panel management activities as well as the perceived challenge associated with caring for patients with particular biomedical, demographic, and psychosocial characteristics (n = 185). Survey results were combined with EHR data at the individual patient and PCP service levels to assess PCP panel workload, accounting for face-to-face and non-face-to-face utilization. Of the multiple face-to-face and non-face-to-face activities associated with routine primary care, PCPs considered hospital admissions, obstetric care, hospital discharges, and new patient preventive health visits to be greater workload than non-face-to-face activities such as telephone calls, electronic communication, generating letters, and medication refills. Total workload within PCP panels at the individual patient level varied by overall health status, and the total workload of non-face-to-face panel management activities associated with routine primary care was greater than the total workload associated with face-to-face encounters regardless of health status. We used PCP survey results coupled with EHR data to assess PCP workload associated with both face-to-face as well as non-face-to-face panel management

  6. Curriculum Change Management and Workload

    ERIC Educational Resources Information Center

    Alkahtani, Aishah

    2017-01-01

    This study examines the ways in which Saudi teachers have responded or are responding to the challenges posed by a new curriculum. It also deals with issues relating to workload demands which affect teachers' performance when they apply a new curriculum in a Saudi Arabian secondary school. In addition, problems such as scheduling and sharing space…

  7. Pilot and Controller Workload and Situation Awareness with Three Traffic Management Concept

    NASA Technical Reports Server (NTRS)

    Vu, Kim-Phuong L.; Strybel, Thomas Z.; Kraut, Joshua; Bacon, Paige; Minakata, Katsumi; Battiste, Vernol; Johnson, Walter

    2010-01-01

    This paper reports on workload and situation awareness of pilots and controllers participating in a human-in-the-loop simulation using three different distributed air-ground traffic management concepts. Eight experimental pilots started the scenario in an en-route phase of flight and were asked to avoid convective weather while performing spacing and merging tasks along with a continuous descent approach (CDA) into Louisville Standiford Airport (SDF). Two controllers managed the sectors through which the pilots flew, with one managing a sector that included the Top of Descent, and the other managing a sector that included the merge point for arrival into SDF. At 3-minute intervals in the scenario, pilots and controllers were probed on their workload or situation awareness. We employed one of three concepts of operation that distributed separation responsibility across human controllers, pilots, and automation to measure changes in operator situation awareness and workload. We found that when pilots were responsible for separation, they had higher levels of awareness, but not necessarily higher levels of workload. When controllers are responsible and actively engaged, they showed higher workload levels compared to pilots and changes in awareness that were dependent on sector characteristics.

  8. Excitation functions of nuclear reactions induced by alpha particles up to 42 MeV on natTi for monitoring purposes and TLA

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Sonck, M.; Takács, S.; Szelecsényi, F.; Tárkányi, F.

    1999-05-01

    Excitation functions for the reactions induced by alpha particles on natTi foils and leading to the formation of 44m,44g,46,47,48Sc; 48,51Cr and 48V were determined using the stacked foil technique for energies from the respective reaction thresholds up to 42 MeV. The new experimental values are compared to earlier literature values and generally good accordance is found. It appears that the natTi(α,x) 51Cr reaction is particularly useful for monitoring α-beams in the 10-20 MeV region while for energies above 20 MeV the natTi(α,x) 47Sc reaction or the natTi(α,x) 48V reaction are more suited. The excitation functions established can be used to determine calibration curves for thin layer activation (TLA) as well.

  9. Comparing capacity coefficient and dual task assessment of visual multitasking workload

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blaha, Leslie M.

    Capacity coefficient analysis could offer a theoretically grounded alternative approach to subjective measures and dual task assessment of cognitive workload. Workload capacity or workload efficiency is a human information processing modeling construct defined as the amount of information that can be processed by the visual cognitive system given a specified of amount of time. In this paper, I explore the relationship between capacity coefficient analysis of workload efficiency and dual task response time measures. To capture multitasking performance, I examine how the relatively simple assumptions underlying the capacity construct generalize beyond the single visual decision making tasks. The fundamental toolsmore » for measuring workload efficiency are the integrated hazard and reverse hazard functions of response times, which are defined by log transforms of the response time distribution. These functions are used in the capacity coefficient analysis to provide a functional assessment of the amount of work completed by the cognitive system over the entire range of response times. For the study of visual multitasking, capacity coefficient analysis enables a comparison of visual information throughput as the number of tasks increases from one to two to any number of simultaneous tasks. I illustrate the use of capacity coefficients for visual multitasking on sample data from dynamic multitasking in the modified Multi-attribute Task Battery.« less

  10. The impact of workload on the ability to localize audible alarms.

    PubMed

    Edworthy, Judy; Reid, Scott; Peel, Katie; Lock, Samantha; Williams, Jessica; Newbury, Chloe; Foster, Joseph; Farrington, Martin

    2018-10-01

    Very little is known about people's ability to localize sound under varying workload conditions, though it would be expected that increasing workload should degrade performance. A set of eight auditory clinical alarms already known to have relatively high localizability (the ease with which their location is identified) when tested alone were tested in six conditions where workload was varied. Participants were required to indicate the location of a series of alarms emanating at random from one of eight speaker locations. Additionally, they were asked to read, carry out mental arithmetic tasks, be exposed to typical ICU noise, or carry out either the reading task or the mental arithmetic task in ICU noise. Performance in the localizability task was best in the control condition (no secondary task) and worst in those tasks which involved both a secondary task and noise. The data does therefore demonstrate the typical pattern of increasing workload affecting a primary task in an area where there is little data. In addition, the data demonstrates that performance in the control condition results in a missed alarm on one in ten occurrences, whereas performance in the heaviest workload conditions results in a missed alarm on every fourth occurrence. This finding has implications for the understanding of both 'inattentional deafness' and 'alarm fatigue' in clinical environments. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Scheduling multicore workload on shared multipurpose clusters

    NASA Astrophysics Data System (ADS)

    Templon, J. A.; Acosta-Silva, C.; Flix Molina, J.; Forti, A. C.; Pérez-Calero Yzquierdo, A.; Starink, R.

    2015-12-01

    With the advent of workloads containing explicit requests for multiple cores in a single grid job, grid sites faced a new set of challenges in workload scheduling. The most common batch schedulers deployed at HEP computing sites do a poor job at multicore scheduling when using only the native capabilities of those schedulers. This paper describes how efficient multicore scheduling was achieved at the sites the authors represent, by implementing dynamically-sized multicore partitions via a minimalistic addition to the Torque/Maui batch system already in use at those sites. The paper further includes example results from use of the system in production, as well as measurements on the dependence of performance (especially the ramp-up in throughput for multicore jobs) on node size and job size.

  12. The prevalence differences of musculoskeletal problems and related physical workload among hospital staff.

    PubMed

    Genç, Arzu; Kahraman, Turhan; Göz, Evrim

    2016-08-10

    The musculoskeletal problems (MSP) vary among different occupations since they had different characteristics and physical workloads. Therefore, it is important to know the difference between the occupational groups to design preventing physiotherapy interventions. To investigate the prevalence differences of MSPs and related physical workload among hospital staff. In this cross-sectional study, 416 hospital staff completed the Nordic Musculoskeletal Questionnaire for MSP and Physical Workload Questionnaire for assessing the physical workload. One-year prevalence of low back, neck, upper back, and shoulders were 73.8%, 59.9%, 59.4%, and 52.2%, respectively. The most preventing MSPs from work found in the low back (39.2%), upper back (26.7%), and the neck (24.5%). MSP of low back impacted nurses the most with a 1-year prevalence of 81.3% and 57.1% of nurses were prevented from working. Nurses, service and cleaning staff had significantly more physical workload than secretaries and physicians. MSP of low back had the highest prevalence among hospital staff and it was the leading cause which prevented from working. Nurses were the most in danger in terms of MSPs among hospital staff. Physical workload was significantly higher in nurses, service and cleaning staff than secretaries and physicians.

  13. Pilot mental workload: how well do pilots really perform?

    PubMed

    Morris, Charles H; Leung, Ying K

    2006-12-15

    The purpose of this study was to investigate the effects of increasing mental demands on various aspects of aircrew performance. In particular, the robustness of the prioritization and allocation hierarchy of aviate-navigate-communicate was examined, a hierarchy commonly used within the aviation industry. A total of 42 trainee pilots were divided into three workload groups (low, medium, high) to complete a desktop, computer-based exercise that simulated combinations of generic flight deck activities: flight control manipulation, rule-based actions and higher level cognitive processing, in addition to Air Traffic Control instructions that varied in length from one chunk of auditory information to seven chunks. It was found that as mental workload and auditory input increased, participants experienced considerable difficulty in carrying out the primary manipulation task. A similar decline in prioritization was also observed. Moreover, when pilots were under a high mental workload their ability to comprehend more than two chunks of auditory data deteriorated rapidly.

  14. Heavy physician workloads: impact on physician attitudes and outcomes.

    PubMed

    Williams, Eric S; Rondeau, Kent V; Xiao, Qian; Francescutti, Louis H

    2007-11-01

    The intensity of physician workload has been increasing with the well-documented changes in the financing, organization and delivery of care. It is possible that these stressors have reached a point where they pose a serious policy issue for the entire healthcare system through their diminution of physician's ability to effectively interact with patients as they are burned out, stressed and dissatisfied. This policy question is framed in a conceptual model linking workloads with five key outcomes (patient care quality, individual performance, absenteeism, turnover and organizational performance) mediated by physician stress and satisfaction. This model showed a good fit to the data in a structural equation analysis. Ten of the 12 hypothesized pathways between variables were significant and supported the mediating role of stress and satisfaction. These results suggest that workloads, stress and satisfaction have significant and material impacts on patient care quality, individual performance, absenteeism, turnover and organizational performance. Implications of these results and directions for future research are discussed.

  15. GP views on strategies to cope with increasing workload: a qualitative interview study.

    PubMed

    Fisher, Rebecca Fr; Croxson, Caroline Hd; Ashdown, Helen F; Hobbs, Fd Richard

    2017-02-01

    The existence of a crisis in primary care in the UK is in little doubt. GP morale and job satisfaction are low, and workload is increasing. In this challenging context, finding ways for GPs to manage that workload is imperative. To explore what existing or potential strategies are described by GPs for dealing with their workload, and their views on the relative merits of each. Semi-structured, qualitative interviews with GPs working within NHS England. All GPs working within NHS England were eligible. Of those who responded to advertisements, a maximum-variation sample was selected and interviewed until data saturation was reached. Data were analysed thematically. Responses were received from 171 GPs, and, from these, 34 were included in the study. Four main themes emerged for workload management: patient-level, GP-level, practice-level, and systems-level strategies. A need for patients to take greater responsibility for self-management was clear, but many felt that GPs should not be responsible for this education. Increased delegation of tasks was felt to be key to managing workload, with innovative use of allied healthcare professionals and extended roles for non-clinical staff suggested. Telephone triage was a commonly used tool for managing workload, although not all participants found this helpful. This in-depth qualitative study demonstrates an encouraging resilience among GPs. They are proactively trying to manage workload, often using innovative local strategies. GPs do not feel that they can do this alone, however, and called repeatedly for increased recruitment and more investment in primary care. © British Journal of General Practice 2017.

  16. Prediction of Traffic Complexity and Controller Workload in Mixed Equipage NextGen Environments

    NASA Technical Reports Server (NTRS)

    Lee, Paul U.; Prevot, Thomas

    2012-01-01

    Controller workload is a key factor in limiting en route air traffic capacity. Past efforts to quantify and predict workload have resulted in identifying objective metrics that correlate well with subjective workload ratings during current air traffic control operations. Although these metrics provide a reasonable statistical fit to existing data, they do not provide a good mechanism for estimating controller workload for future air traffic concepts and environments that make different assumptions about automation, enabling technologies, and controller tasks. One such future environment is characterized by en route airspace with a mixture of aircraft equipped with and without Data Communications (Data Comm). In this environment, aircraft with Data Comm will impact controller workload less than aircraft requiring voice communication, altering the close correlation between aircraft count and controller workload that exists in current air traffic operations. This paper outlines a new trajectory-based complexity (TBX) calculation that was presented to controllers during a human-in-the-loop simulation. The results showed that TBX accurately estimated the workload in a mixed Data Comm equipage environment and the resulting complexity values were understood and readily interpreted by the controllers. The complexity was represented as a "modified aircraft account" that weighted different complexity factors and summed them in such a way that the controllers could effectively treat them as aircraft count. The factors were also relatively easy to tune without an extensive data set. The results showed that the TBX approach is well suited for presenting traffic complexity in future air traffic environments.

  17. Patient Safety Incidents and Nursing Workload.

    PubMed

    Carlesi, Katya Cuadros; Padilha, Kátia Grillo; Toffoletto, Maria Cecília; Henriquez-Roldán, Carlos; Juan, Monica Andrea Canales

    2017-04-06

    to identify the relationship between the workload of the nursing team and the occurrence of patient safety incidents linked to nursing care in a public hospital in Chile. quantitative, analytical, cross-sectional research through review of medical records. The estimation of workload in Intensive Care Units (ICUs) was performed using the Therapeutic Interventions Scoring System (TISS-28) and for the other services, we used the nurse/patient and nursing assistant/patient ratios. Descriptive univariate and multivariate analysis were performed. For the multivariate analysis we used principal component analysis and Pearson correlation. 879 post-discharge clinical records and the workload of 85 nurses and 157 nursing assistants were analyzed. The overall incident rate was 71.1%. It was found a high positive correlation between variables workload (r = 0.9611 to r = 0.9919) and rate of falls (r = 0.8770). The medication error rates, mechanical containment incidents and self-removal of invasive devices were not correlated with the workload. the workload was high in all units except the intermediate care unit. Only the rate of falls was associated with the workload. identificar a relação entre a carga de trabalho da equipe de enfermagem e a ocorrência de incidentes de segurança dos pacientes ligados aos cuidados de enfermagem de um hospital público no Chile. pesquisa transversal analítica quantitativa através de revisão de prontuários médicos. A estimativa da carga de trabalho em Unidade de Terapia Intensiva (UTI) foi realizada utilizando o Índice de Intervenções Terapêuticas-TISS-28 e para os outros serviços, foram utilizados os cocientes enfermeira/paciente e auxiliar de enfermagem/ paciente. Foram feitas análises univariada descritiva e multivariada. Para a análise multivariada utilizou-se análise de componentes principais e correlação de Pearson. foram analisados 879 prontuáriosclínicos de pós-alta e a carga de trabalho de 85 enfermeiros e 157

  18. Understanding I/O workload characteristics of a Peta-scale storage system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Youngjae; Gunasekaran, Raghul

    2015-01-01

    Understanding workload characteristics is critical for optimizing and improving the performance of current systems and software, and architecting new storage systems based on observed workload patterns. In this paper, we characterize the I/O workloads of scientific applications of one of the world s fastest high performance computing (HPC) storage cluster, Spider, at the Oak Ridge Leadership Computing Facility (OLCF). OLCF flagship petascale simulation platform, Titan, and other large HPC clusters, in total over 250 thousands compute cores, depend on Spider for their I/O needs. We characterize the system utilization, the demands of reads and writes, idle time, storage space utilization,more » and the distribution of read requests to write requests for the Peta-scale Storage Systems. From this study, we develop synthesized workloads, and we show that the read and write I/O bandwidth usage as well as the inter-arrival time of requests can be modeled as a Pareto distribution. We also study the I/O load imbalance problems using I/O performance data collected from the Spider storage system.« less

  19. Bioinstrumentation for evaluation of workload in payload specialists - Results of ASSESS II

    NASA Technical Reports Server (NTRS)

    Wegmann, H. M.; Herrmann, R.; Winget, C. M.

    1979-01-01

    Results of the medical experiment on payload specialist workloads conducted as part of the ASSESS II airborne simulation of Spacelab conditions are reported. Subjects were fitted with temperature probes and ECG, EEG and EOG electrodes, and hormone and electrolyte excretion was monitored in order to evaluate the changes in circadian rhythms, sleep patterns and stress responses brought about by mission schedules over the ten days of the experiment. Internal dissociations of circadian rhythms, sleep disturbances and increased stress levels were observed, especially during the first three days of the experiment, indicating a considerable workload to be imposed upon the payload specialists. An intensive premission simulation is suggested as a means of estimating overall workloads and allowing payload specialist adaptation to mission conditions. The bioinstrumentation which was developed and applied to the airborne laboratory is concluded to be a practical and reliable tool in the assessment of payload specialist workloads.

  20. Measuring Workload Demand of Informatics Systems with the Clinical Case Demand Index

    PubMed Central

    Iyengar, M. Sriram; Rogith, Deevakar; Florez-Arango, Jose F

    2017-01-01

    Introduction: The increasing use of Health Information Technology (HIT) can add substantially to workload on clinical providers. Current methods for assessing workload do not take into account the nature of clinical cases and the use of HIT tools while solving them. Methods: The Clinical Case Demand Index (CCDI), consisting of a summary score and visual representation, was developed to meet this need. Consistency with current perceived workload measures was evaluated in a Randomized Control Trial of a mobile health system. Results: CCDI is significantly correlated with existing workload measures and inversely related to provider performance. Discussion: CCDI combines subjective and objective characteristics of clinical cases along with cognitive and clinical dimensions. Applications include evaluation of HIT tools, clinician scheduling, medical education. Conclusion: CCDI supports comparative effectiveness research of HIT tools. In addition, CCDI could have numerous applications including training, clinical trials, design of clinical workflows, and others. PMID:29854166

  1. Commissioning the CERN IT Agile Infrastructure with experiment workloads

    NASA Astrophysics Data System (ADS)

    Medrano Llamas, Ramón; Harald Barreiro Megino, Fernando; Kucharczyk, Katarzyna; Kamil Denis, Marek; Cinquilli, Mattia

    2014-06-01

    In order to ease the management of their infrastructure, most of the WLCG sites are adopting cloud based strategies. In the case of CERN, the Tier 0 of the WLCG, is completely restructuring the resource and configuration management of their computing center under the codename Agile Infrastructure. Its goal is to manage 15,000 Virtual Machines by means of an OpenStack middleware in order to unify all the resources in CERN's two datacenters: the one placed in Meyrin and the new on in Wigner, Hungary. During the commissioning of this infrastructure, CERN IT is offering an attractive amount of computing resources to the experiments (800 cores for ATLAS and CMS) through a private cloud interface. ATLAS and CMS have joined forces to exploit them by running stress tests and simulation workloads since November 2012. This work will describe the experience of the first deployments of the current experiment workloads on the CERN private cloud testbed. The paper is organized as follows: the first section will explain the integration of the experiment workload management systems (WMS) with the cloud resources. The second section will revisit the performance and stress testing performed with HammerCloud in order to evaluate and compare the suitability for the experiment workloads. The third section will go deeper into the dynamic provisioning techniques, such as the use of the cloud APIs directly by the WMS. The paper finishes with a review of the conclusions and the challenges ahead.

  2. Fault and Error Latency Under Real Workload: an Experimental Study. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Chillarege, Ram

    1986-01-01

    A practical methodology for the study of fault and error latency is demonstrated under a real workload. This is the first study that measures and quantifies the latency under real workload and fills a major gap in the current understanding of workload-failure relationships. The methodology is based on low level data gathered on a VAX 11/780 during the normal workload conditions of the installation. Fault occurrence is simulated on the data, and the error generation and discovery process is reconstructed to determine latency. The analysis proceeds to combine the low level activity data with high level machine performance data to yield a better understanding of the phenomena. A strong relationship exists between latency and workload and that relationship is quantified. The sampling and reconstruction techniques used are also validated. Error latency in the memory where the operating system resides was studied using data on the physical memory access. Fault latency in the paged section of memory was determined using data from physical memory scans. Error latency in the microcontrol store was studied using data on the microcode access and usage.

  3. Workload Capacity: A Response Time-Based Measure of Automation Dependence.

    PubMed

    Yamani, Yusuke; McCarley, Jason S

    2016-05-01

    An experiment used the workload capacity measure C(t) to quantify the processing efficiency of human-automation teams and identify operators' automation usage strategies in a speeded decision task. Although response accuracy rates and related measures are often used to measure the influence of an automated decision aid on human performance, aids can also influence response speed. Mean response times (RTs), however, conflate the influence of the human operator and the automated aid on team performance and may mask changes in the operator's performance strategy under aided conditions. The present study used a measure of parallel processing efficiency, or workload capacity, derived from empirical RT distributions as a novel gauge of human-automation performance and automation dependence in a speeded task. Participants performed a speeded probabilistic decision task with and without the assistance of an automated aid. RT distributions were used to calculate two variants of a workload capacity measure, COR(t) and CAND(t). Capacity measures gave evidence that a diagnosis from the automated aid speeded human participants' responses, and that participants did not moderate their own decision times in anticipation of diagnoses from the aid. Workload capacity provides a sensitive and informative measure of human-automation performance and operators' automation dependence in speeded tasks. © 2016, Human Factors and Ergonomics Society.

  4. Field study of communication and workload in police helicopters - Implications for AI cockpit design

    NASA Technical Reports Server (NTRS)

    Linde, Charlotte; Shively, Robert J.

    1988-01-01

    This paper reports on the work performed by civilian helicopter crews, using audio and video recordings and a variety of workload measures (heart rate and subjective ratings) obtained in a field study of public service helicopter missions. The number and frequency of communications provided a significant source of workload. This is relevant to the design of automated cockpit systems, since many designs presuppose the use of voice I/O systems. Fluency of communications (including pauses, hesitation markers, repetitions, and false starts) furnished an early indication of the effects of fatigue. Three workload measures were correlated to identify high workload segments of flight, and to suggest alternate task allocations between crew members.

  5. Scaling deep learning workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gawande, Nitin A.; Landwehr, Joshua B.; Daily, Jeffrey A.

    Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors --- including NVIDIA, Intel, AMD, and IBM --- have architectural road-maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating large DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. This paper provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path or Cray Aries. Ourmore » evaluation consists of a cross section of convolutional neural net workloads: CifarNet, AlexNet, GoogLeNet, and ResNet50 topologies using the Cifar10 and ImageNet datasets. The workloads are vendor-optimized for each architecture. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and the KNL can be competitive in performance/watt. We find that NVLink facilitates scaling efficiency on GPUs. However, its importance is heavily dependent on neural network architecture. Furthermore, for weak-scaling --- sometimes encouraged by restricted GPU memory --- NVLink is less important.« less

  6. Circadian rhythms in myocardial metabolism and contractile function: influence of workload and oleate.

    PubMed

    Durgan, David J; Moore, Michael W S; Ha, Ngan P; Egbejimi, Oluwaseun; Fields, Anna; Mbawuike, Uchenna; Egbejimi, Anu; Shaw, Chad A; Bray, Molly S; Nannegari, Vijayalakshmi; Hickson-Bick, Diane L; Heird, William C; Dyck, Jason R B; Chandler, Margaret P; Young, Martin E

    2007-10-01

    Multiple extracardiac stimuli, such as workload and circulating nutrients (e.g., fatty acids), known to influence myocardial metabolism and contractile function exhibit marked circadian rhythms. The aim of the present study was to investigate whether the rat heart exhibits circadian rhythms in its responsiveness to changes in workload and/or fatty acid (oleate) availability. Thus, hearts were isolated from male Wistar rats (housed during a 12:12-h light-dark cycle: lights on at 9 AM) at 9 AM, 3 PM, 9 PM, and 3 AM and perfused in the working mode ex vivo with 5 mM glucose plus either 0.4 or 0.8 mM oleate. Following 20-min perfusion at normal workload (i.e., 100 cm H(2)O afterload), hearts were challenged with increased workload (140 cm H(2)O afterload plus 1 microM epinephrine). In the presence of 0.4 mM oleate, myocardial metabolism exhibited a marked circadian rhythm, with decreased rates of glucose oxidation, increased rates of lactate release, decreased glycogenolysis capacity, and increased channeling of oleate into nonoxidative pathways during the light phase. Rat hearts also exhibited a modest circadian rhythm in responsiveness to the workload challenge when perfused in the presence of 0.4 mM oleate, with increased myocardial oxygen consumption at the dark-to-light phase transition. However, rat hearts perfused in the presence of 0.8 mM oleate exhibited a markedly blunted contractile function response to the workload challenge during the light phase. In conclusion, these studies expose marked circadian rhythmicities in myocardial oxidative and nonoxidative metabolism as well as responsiveness of the rat heart to changes in workload and fatty acid availability.

  7. Maximizing Efficiency and Reducing Robotic Surgery Costs Using the NASA Task Load Index.

    PubMed

    Walters, Carrie; Webb, Paula J

    2017-10-01

    Perioperative leaders at our facility were struggling to meet efficiency targets for robotic surgery procedures while also maintaining the satisfaction of the surgical team. We developed a human resources time and motion study tool and used it in conjunction with the NASA Task Load Index to observe and analyze the required workload of personnel assigned to 25 robotic surgery procedures. The time and motion study identified opportunities to enlist the help of nonlicensed support personnel to ensure safe patient care and improve OR efficiency. Using the NASA Task Load Index demonstrated that high temporal, effort, and physical demands existed for personnel assisting with and performing robotic surgery. We believe that this process could be used to develop cost-effective staffing models, resulting in safe and efficient care for all surgical patients. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  8. Comparative Staffing Units as a Measure of University Instructional Workload. Second Edition.

    ERIC Educational Resources Information Center

    Colorado State Univ., Ft. Collins.

    A project was undertaken to devise an improved method for determining the workload generated by each direct instructional, instructional-related, and professional-related activity carried out at Colorado State University and the estimated workload expected of each instructional faculty member. These load factors specifically recognize the input…

  9. Predictors of nursing workload in elderly patients admitted to intensive care units.

    PubMed

    Sousa, Cleber Ricardo de; Gonçalves, Leilane Andrade; Toffoleto, Maria Cecília; Leão, Karine; Padilha, Kátia Grillo

    2008-01-01

    The age of patients is a controversial issue in admission to intensive care unit (ICU). The aim of this study was to compare severity and nursing workload of elderly patients with 60-69, 70-79, and e"80 years of age and to identify predictors of nursing workload in elderly patients. A cross sectional study was performed with a sample of 71 elderly patients admitted to three ICU in the city of Sao Paulo, Brazil from October to November 2004. Data were prospectively collected using Nursing Activities Score (NAS) and Simplified Acute Physiology Score II (SAPS II). There was no significant difference in nursing workload among the elderly patients age subgroups (p=0.84). Multiple regression analysis indicated that the independent risk factors of high nursing workload were severity, age e"70 years, and to be a surgical ICU patient. Age as an isolated factor should not be discriminative for elderly patients admission to ICU.

  10. Effects of workload on teachers' functioning: A moderated mediation model including sleeping problems and overcommitment.

    PubMed

    Huyghebaert, Tiphaine; Gillet, Nicolas; Beltou, Nicolas; Tellier, Fanny; Fouquereau, Evelyne

    2018-06-14

    This study investigated the mediating role of sleeping problems in the relationship between workload and outcomes (emotional exhaustion, presenteeism, job satisfaction, and performance), and overcommitment was examined as a moderator in the relationship between workload and sleeping problems. We conducted an empirical study using a sample of 884 teachers. Consistent with our predictions, results revealed that the positive indirect effects of workload on emotional exhaustion and presenteeism, and the negative indirect effects of workload on job satisfaction and performance, through sleeping problems, were only significant among overcommitted teachers. Workload and overcommitment were also directly related to all four outcomes, precisely, they both positively related to emotional exhaustion and presenteeism and negatively related to job satisfaction and performance. Theoretical contributions and perspectives and implications for practice are discussed. Copyright © 2018 John Wiley & Sons, Ltd.

  11. EEG correlates of task engagement and mental workload in vigilance, learning, and memory tasks.

    PubMed

    Berka, Chris; Levendowski, Daniel J; Lumicao, Michelle N; Yau, Alan; Davis, Gene; Zivkovic, Vladimir T; Olmstead, Richard E; Tremoulet, Patrice D; Craven, Patrick L

    2007-05-01

    The ability to continuously and unobtrusively monitor levels of task engagement and mental workload in an operational environment could be useful in identifying more accurate and efficient methods for humans to interact with technology. This information could also be used to optimize the design of safer, more efficient work environments that increase motivation and productivity. The present study explored the feasibility of monitoring electroencephalo-graphic (EEG) indices of engagement and workload acquired unobtrusively and quantified during performance of cognitive tests. EEG was acquired from 80 healthy participants with a wireless sensor headset (F3-F4,C3-C4,Cz-POz,F3-Cz,Fz-C3,Fz-POz) during tasks including: multi-level forward/backward-digit-span, grid-recall, trails, mental-addition, 20-min 3-Choice Vigilance, and image-learning and memory tests. EEG metrics for engagement and workload were calculated for each 1 -s of EEG. Across participants, engagement but not workload decreased over the 20-min vigilance test. Engagement and workload were significantly increased during the encoding period of verbal and image-learning and memory tests when compared with the recognition/ recall period. Workload but not engagement increased linearly as level of difficulty increased in forward and backward-digit-span, grid-recall, and mental-addition tests. EEG measures correlated with both subjective and objective performance metrics. These data in combination with previous studies suggest that EEG engagement reflects information-gathering, visual processing, and allocation of attention. EEG workload increases with increasing working memory load and during problem solving, integration of information, analytical reasoning, and may be more reflective of executive functions. Inspection of EEG on a second-by-second timescale revealed associations between workload and engagement levels when aligned with specific task events providing preliminary evidence that second

  12. Measurement of operator workload in an information processing task

    NASA Technical Reports Server (NTRS)

    Jenney, L. L.; Older, H. J.; Cameron, B. J.

    1972-01-01

    This was an experimental study to develop an improved methodology for measuring workload in an information processing task and to assess the effects of shift length and communication density (rate of information flow) on the ability to process and classify verbal messages. Each of twelve subjects was exposed to combinations of three shift lengths and two communication densities in a counterbalanced, repeated measurements experimental design. Results indicated no systematic variation in task performance measures or in other dependent measures as a function of shift length or communication density. This is attributed to the absence of a secondary loading task, an insufficiently taxing work schedule, and the lack of psychological stress. Subjective magnitude estimates of workload showed fatigue (and to a lesser degree, tension) to be a power function of shift length. Estimates of task difficulty and fatigue were initially lower but increased more sharply over time under low density than under high density conditions. An interpretation of findings and recommedations for furture research are included. This research has major implications to human workload problems in information processing of air traffic control verbal data.

  13. Driver's workload comparison in waste collection vehicle routing problem

    NASA Astrophysics Data System (ADS)

    Benjamin, Aida Mauziah; Abdul-Rahman, Syariza

    2016-10-01

    This paper compares the workload of the drivers for a waste collection benchmark problem. The problem involves ten data sets with different number of customers to be served and different number of disposal facilities available. Previous studies proposed a heuristic algorithm, namely Different Initial Customer (DIC) to solve the problem by constructing initial vehicles routes for the drivers with two main objectives; to minimize the total distance travelled and to minimize the total number of vehicles needed to collect the waste. The results from DIC compared well with other solutions in the literature. However, the balance of the workload among the vehicle drivers is not considered in the solutions. Thus in this paper, we evaluate the quality of the solutions in terms of the total number of customers served by each driver. Then the computational result is compared in terms of the total distance travelled which have been presented in a previous study. Comparison results show that the workload of the drivers are unbalance in terms of these two factors that may cause dissatisfaction among the drivers as well as to the managament.

  14. Adult social position and sick leave: the mediating effect of physical workload.

    PubMed

    Corbett, Karina; Gran, Jon Michaeal; Kristensen, Petter; Mehlum, Ingrid Sivesind

    2015-11-01

    This study aimed to quantify how much of the adult social gradient in sick leave can be attributed to the mediating role of physical workload while accounting for the role of childhood and adolescent social position and neuroticism. Our sample consisted of 2099 women and 1229 men from a Norwegian birth cohort study (born 1967-1976) who participated in the Nord-Trøndelag Health Study (2006-2008) (HUNT3). Data on sick leave (defined as >16 calendar days; 2006-2009) and social position during childhood, adolescence, and adulthood were obtained from national registers. Study outcome was time-to-first sick leave spell. Physical workload and neuroticism were self-reported in HUNT3. Mediating effects through physical workload were estimated using a method based on the additive hazards survival model. A hypothetical change from highest to lowest group in adult social position was, for women, associated with 51.6 [95% confidence interval (95% CI) 24.7-78.5] additional spells per 100,000 person-days at risk, in a model adjusted for childhood and adolescent social position and neuroticism. The corresponding rate increase for men was 41.1 (95% CI 21.4-60.8). Of these additional spells, the proportion mediated through physical workload was 24% (95% CI 10-49) and 30% (95% CI 10-63) for women and men, respectively. The effect of adult social position on sick leave was partly mediated through physical workload, even while accounting for earlier life course factors. Our findings provide support that interventions aimed at reducing physical workload among those with lower adult social position could reduce sick leave risk.

  15. A reliability-based maintenance technicians' workloads optimisation model with stochastic consideration

    NASA Astrophysics Data System (ADS)

    Ighravwe, D. E.; Oke, S. A.; Adebiyi, K. A.

    2016-06-01

    The growing interest in technicians' workloads research is probably associated with the recent surge in competition. This was prompted by unprecedented technological development that triggers changes in customer tastes and preferences for industrial goods. In a quest for business improvement, this worldwide intense competition in industries has stimulated theories and practical frameworks that seek to optimise performance in workplaces. In line with this drive, the present paper proposes an optimisation model which considers technicians' reliability that complements factory information obtained. The information used emerged from technicians' productivity and earned-values using the concept of multi-objective modelling approach. Since technicians are expected to carry out routine and stochastic maintenance work, we consider these workloads as constraints. The influence of training, fatigue and experiential knowledge of technicians on workload management was considered. These workloads were combined with maintenance policy in optimising reliability, productivity and earned-values using the goal programming approach. Practical datasets were utilised in studying the applicability of the proposed model in practice. It was observed that our model was able to generate information that practicing maintenance engineers can apply in making more informed decisions on technicians' management.

  16. Role of Academic Managers in Workload and Performance Management of Academic Staff: A Case Study

    ERIC Educational Resources Information Center

    Graham, Andrew T.

    2016-01-01

    This small-scale case study focused on academic managers to explore the ways in which they control the workload of academic staff and the extent to which they use the workload model in performance management of academic staff. The links that exist between the workload and performance management were explored to confirm or refute the conceptual…

  17. Perceptions of mental workload in Dutch university employees of different ages: a focus group study.

    PubMed

    Bos, Judith T; Donders, Nathalie C G M; van der Velden, Koos; van der Gulden, Joost W J

    2013-03-18

    As academic workload seems to be increasing, many studies examined factors that contribute to the mental workload of academics. Age-related differences in work motives and intellectual ability may lead to differences in experienced workload and in the way employees experience work features. This study aims to obtain a better understanding of age differences in sources of mental workload. 33 academics from one faculty discussed causes of workload during focus group interviews, stratified by age. Among our participants, the influence of ageing seems most evident in employees' actions and reactions, while the causes of workload mentioned seemed largely similar. These individual reactions to workload may also be driven by differences in tenure. Most positively assessed work characteristics were: interaction with colleagues and students and autonomy. Aspects most often indicated as increasing the workload, were organisational aspects as obstacles for 'getting the best out of people' and the feeling that overtime seems unavoidable. Many employees indicated to feel stretched between the 'greediness' of the organisation and their own high working standards, and many fear to be assigned even less time for research if they do not meet the rigorous output criteria. Moreover, despite great efforts on their part, promotion opportunities seem limited. A more pronounced role for the supervisor seems appreciated by employees of all ages, although the specific interpretation varied between individuals and career stages. To preserve good working conditions and quality of work, it seems important to scrutinize the output requirements and tenure-based needs for employee supervision.

  18. Perceptions of mental workload in Dutch university employees of different ages: a focus group study

    PubMed Central

    2013-01-01

    Background As academic workload seems to be increasing, many studies examined factors that contribute to the mental workload of academics. Age-related differences in work motives and intellectual ability may lead to differences in experienced workload and in the way employees experience work features. This study aims to obtain a better understanding of age differences in sources of mental workload. 33 academics from one faculty discussed causes of workload during focus group interviews, stratified by age. Findings Among our participants, the influence of ageing seems most evident in employees’ actions and reactions, while the causes of workload mentioned seemed largely similar. These individual reactions to workload may also be driven by differences in tenure. Most positively assessed work characteristics were: interaction with colleagues and students and autonomy. Aspects most often indicated as increasing the workload, were organisational aspects as obstacles for ‘getting the best out of people’ and the feeling that overtime seems unavoidable. Many employees indicated to feel stretched between the ‘greediness’ of the organisation and their own high working standards, and many fear to be assigned even less time for research if they do not meet the rigorous output criteria. Moreover, despite great efforts on their part, promotion opportunities seem limited. A more pronounced role for the supervisor seems appreciated by employees of all ages, although the specific interpretation varied between individuals and career stages. Conclusions To preserve good working conditions and quality of work, it seems important to scrutinize the output requirements and tenure-based needs for employee supervision. PMID:23506458

  19. Intra-operative disruptions, surgeon's mental workload, and technical performance in a full-scale simulated procedure.

    PubMed

    Weigl, Matthias; Stefan, Philipp; Abhari, Kamyar; Wucherer, Patrick; Fallavollita, Pascal; Lazarovici, Marc; Weidert, Simon; Euler, Ekkehard; Catchpole, Ken

    2016-02-01

    Surgical flow disruptions occur frequently and jeopardize perioperative care and surgical performance. So far, insights into subjective and cognitive implications of intra-operative disruptions for surgeons and inherent consequences for performance are inconsistent. This study aimed to investigate the effect of surgical flow disruption on surgeon's intra-operative workload and technical performance. In a full-scale OR simulation, 19 surgeons were randomly allocated to either of the two disruption scenarios (telephone call vs. patient discomfort). Using a mixed virtual reality simulator with a computerized, high-fidelity mannequin, all surgeons were trained in performing a vertebroplasty procedure and subsequently performed such a procedure under experimental conditions. Standardized measures on subjective workload and technical performance (trocar positioning deviation from expert-defined standard, number, and duration of X-ray acquisitions) were collected. Intra-operative workload during simulated disruption scenarios was significantly higher compared to training sessions (p < .01). Surgeons in the telephone call scenario experienced significantly more distraction compared to their colleagues in the patient discomfort scenario (p < .05). However, workload tended to be increased in surgeons who coped with distractions due to patient discomfort. Technical performance was not significantly different between both disruption scenarios. We found a significant association between surgeons' intra-operative workload and technical performance such that surgeons with increased mental workload tended to perform worse (β = .55, p = .04). Surgical flow disruptions affect surgeons' intra-operative workload. Increased mental workload was associated with inferior technical performance. Our simulation-based findings emphasize the need to establish smooth surgical flow which is characterized by a low level of process deviations and disruptions.

  20. Heavy vehicle driver workload assessment : executive summary

    DOT National Transportation Integrated Search

    1996-10-01

    This report summarizes a program of research to develop methods, data, and guidelines to conduct heavy vehicle driver-oriented workload assessments of new, high-technology, in-cab devices. Many such devices are being developed and implemented in heav...

  1. An investigation of the 'von Restorff' phenomenon in post-test workload ratings

    NASA Technical Reports Server (NTRS)

    Thornton, D. C.

    1985-01-01

    The von Restorff effect in post-task ratings of task difficulty is examined. Nine subjects performed a hovercraft simulation task which combined elements of skill-based tracking and rule- and knowledge-based process control for five days of one hour sessions. The effects of isolated increases in workload on rating of task performance, and on the number of command errors and river band hits are analyzed. It is observed that the position of the workload increase affects the number of bank hits and command errors. The data reveal that factors not directly related to the task performance influence subjective rating, and post-task ratings of workload are biased.

  2. The Influence of Nursing Faculty Workloads on Faculty Retention: A Case Study

    ERIC Educational Resources Information Center

    Wood, Jennifer J.

    2013-01-01

    Nursing faculty workloads have come to the forefront of discussion in nursing education. The National League of Nursing (NLN) has made nursing faculty workloads a high priority in nursing education. Included in the priorities are areas of creating reform through innovations in nursing education, evaluating reform through evaluation research, and…

  3. Shift manager workload assessment - A case study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berntson, K.; Kozak, A.; Malcolm, J. S.

    2006-07-01

    In early 2003, Bruce Power restarted two of its previously laid up units in the Bruce A generating station, Units 3 and 4. However, due to challenges relating to the availability of personnel with active Shift Manager licenses, an alternate shift structure was proposed to ensure the safe operation of the station. This alternate structure resulted in a redistribution of responsibility, and a need to assess the resulting changes in workload. Atomic Energy of Canada Limited was contracted to perform a workload assessment based on the new shift structure, and to provide recommendations, if necessary, to ensure Shift Managers hadmore » sufficient resources available to perform their required duties. This paper discusses the performance of that assessment, and lessons learned as a result of the work performed during the Restart project. (authors)« less

  4. Scaling Deep Learning workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing

    DOE PAGES

    Gawande, Nitin A.; Daily, Jeff A.; Siegel, Charles; ...

    2018-05-05

    Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors—including NVIDIA, Intel, AMD, and IBM—have architectural road maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating large DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. Here, this article provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path or Cray Aries. Our evaluation consistsmore » of a cross section of convolutional neural net workloads: CifarNet, AlexNet, GoogLeNet, and ResNet50 topologies using the Cifar10 and ImageNet datasets. The workloads are vendor-optimized for each architecture. We use sequentially equivalent implementations to maintain iso-accuracy between parallel and sequential DL models. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and the KNL can be competitive in performance/watt. We find that NVLink facilitates scaling efficiency on GPUs. However, its importance is heavily dependent on neural network architecture. Furthermore, for weak-scaling—sometimes encouraged by restricted GPU memory—NVLink is less important.« less

  5. Scaling Deep Learning workloads: NVIDIA DGX-1/Pascal and Intel Knights Landing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gawande, Nitin A.; Daily, Jeff A.; Siegel, Charles

    Deep Learning (DL) algorithms have become ubiquitous in data analytics. As a result, major computing vendors—including NVIDIA, Intel, AMD, and IBM—have architectural road maps influenced by DL workloads. Furthermore, several vendors have recently advertised new computing products as accelerating large DL workloads. Unfortunately, it is difficult for data scientists to quantify the potential of these different products. Here, this article provides a performance and power analysis of important DL workloads on two major parallel architectures: NVIDIA DGX-1 (eight Pascal P100 GPUs interconnected with NVLink) and Intel Knights Landing (KNL) CPUs interconnected with Intel Omni-Path or Cray Aries. Our evaluation consistsmore » of a cross section of convolutional neural net workloads: CifarNet, AlexNet, GoogLeNet, and ResNet50 topologies using the Cifar10 and ImageNet datasets. The workloads are vendor-optimized for each architecture. We use sequentially equivalent implementations to maintain iso-accuracy between parallel and sequential DL models. Our analysis indicates that although GPUs provide the highest overall performance, the gap can close for some convolutional networks; and the KNL can be competitive in performance/watt. We find that NVLink facilitates scaling efficiency on GPUs. However, its importance is heavily dependent on neural network architecture. Furthermore, for weak-scaling—sometimes encouraged by restricted GPU memory—NVLink is less important.« less

  6. Workload Management Strategies for Online Educators

    ERIC Educational Resources Information Center

    Crews, Tena B.; Wilkinson, Kelly; Hemby, K. Virginia; McCannon, Melinda; Wiedmaier, Cheryl

    2008-01-01

    With increased use of online education, both students and instructors are adapting to the online environment. Online educators must adjust to the change in responsibilities required to teach online, as it is quite intensive during the designing, teaching, and revising stages. The purpose of this study is to examine and update workload management…

  7. A Review of Faculty Workload Policies and Faculty Workloads at the University of Massachusetts at Amherst. Report of the Select Committee on Post Audit and Oversight. Senate No. 1785.

    ERIC Educational Resources Information Center

    Massachusetts State Legislature, Boston. Senate Committee on Post Audit and Oversight.

    This Massachusetts Senate committee study examined the current policies and procedures used by the University of Massachusetts at Amherst (UMA) to monitor, manage, and report on the activities of its faculty, in particular its faculty workload. The study had originally intended to analyze faculty workload in terms of instruction (teaching),…

  8. 78 FR 19329 - Request for Information (RFI): Reducing Investigator's Administrative Workload for Federally...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... most to their administrative workload and to offer recommendations for reducing that workload. Members... offer recommendations to reduce unnecessary and redundant administrative requirements. Background Over... an awardee's available research time, a figure widely cited in numerous articles and reports. To help...

  9. EEG Estimates of Cognitive Workload and Engagement Predict Math Problem Solving Outcomes

    ERIC Educational Resources Information Center

    Beal, Carole R.; Galan, Federico Cirett

    2012-01-01

    In the present study, the authors focused on the use of electroencephalography (EEG) data about cognitive workload and sustained attention to predict math problem solving outcomes. EEG data were recorded as students solved a series of easy and difficult math problems. Sequences of attention and cognitive workload estimates derived from the EEG…

  10. Workload and Marital Satisfaction over Time: Testing Lagged Spillover and Crossover Effects during the Newlywed Years.

    PubMed

    Lavner, Justin A; Clark, Malissa A

    2017-08-01

    Although many studies have found that higher workloads covary with lower levels of marital satisfaction, the question of whether workloads may also predict changes in marital satisfaction over time has been overlooked. To address this question, we investigated the lagged association between own and partner workload and marital satisfaction using eight waves of data collected every 6 months over the first four years of marriage from 172 heterosexual couples. Significant crossover, but not spillover, effects were found, indicating that partners of individuals with higher workloads at one time point experience greater declines in marital satisfaction by the following time point compared to the partners of individuals with lower workloads. These effects were not moderated by gender or parental status. These findings suggest that higher partner workloads can prove deleterious for relationship functioning over time and call for increased attention to the long-term effects of spillover and crossover from work to marital functioning.

  11. Validation of air traffic controller workload models

    DOT National Transportation Integrated Search

    1979-09-01

    During the past several years, computer models have been developed for off-site : estimat ion of control ler's workload. The inputs to these models are audio and : digital data normally recorded at an Air Route Traffic Control Center (ARTCC). : This ...

  12. Cloudweaver: Adaptive and Data-Driven Workload Manager for Generic Clouds

    NASA Astrophysics Data System (ADS)

    Li, Rui; Chen, Lei; Li, Wen-Syan

    Cloud computing denotes the latest trend in application development for parallel computing on massive data volumes. It relies on clouds of servers to handle tasks that used to be managed by an individual server. With cloud computing, software vendors can provide business intelligence and data analytic services for internet scale data sets. Many open source projects, such as Hadoop, offer various software components that are essential for building a cloud infrastructure. Current Hadoop (and many others) requires users to configure cloud infrastructures via programs and APIs and such configuration is fixed during the runtime. In this chapter, we propose a workload manager (WLM), called CloudWeaver, which provides automated configuration of a cloud infrastructure for runtime execution. The workload management is data-driven and can adapt to dynamic nature of operator throughput during different execution phases. CloudWeaver works for a single job and a workload consisting of multiple jobs running concurrently, which aims at maximum throughput using a minimum set of processors.

  13. Influence of patient and provider factors on the workload of on-call physicians

    PubMed Central

    Hsu, Nin-Chieh; Huang, Chun-Che; Jerng, Jih-Shuin; Hsu, Chia-Hao; Yang, Ming-Chin; Chang, Ray-E; Ko, Wen-Je; Yu, Chong-Jen

    2016-01-01

    Abstract Factors associated with the physician workload are scarcely reported. The study aims to investigate the associated factors of on-call physician workload based on a published conceptual framework. The study was conducted in a general internal medicine unit of National Taiwan University Hospital. On-call physician workloads were recorded on a shift basis from 1198 hospitalized patients between May 2010 and April 2011. The proxy of on-call workloads included night calls, bedside evaluation/management (E/M), and performing clinical procedures in a shift. Multivariable logistic and negative binomial regression models were used to determine the factors associated with the workloads of on-call physicians. During the study period, 378 (31.6%) of patients had night calls with related workloads. Multivariate analysis showed that the number of patients with unstable conditions in a shift (odds ratio [OR] 1.89 and 1.66, respectively) and the intensive care unit (ICU) training of the nurse leader (OR 2.87 and 3.08, respectively) resulted in higher likelihood of night calls to and bedside E/M visits by the on-call physician. However, ICU training of nurses (OR = 0.37, 95% confidence interval: 0.16–0.86) decreased the demand of performing clinical procedures by the on-call physician. Moreover, number of patients with unstable conditions (risk ratio [RR] 1.52 and 1.55, respectively) had significantly increased the number of night calls and bedside E/M by on-call physicians by around 50%. Nurses with N1 level (RR 2.16 and 2.71, respectively) were more likely to place night calls and facilitate bedside E/M by the on-call physician compared to nurses with N0 level. In addition, the nurse leaders with ICU training (RR 1.72 and 3.07, respectively) had significant increases in night calls and bedside E/M by the on-call physician compared to those without ICU training. On-call physician workload is associated with patient factors and the training of nurses. Number of

  14. How to reduce workload--augmented reality to ease the work of air traffic controllers.

    PubMed

    Hofmann, Thomas; König, Christina; Bruder, Ralph; Bergner, Jörg

    2012-01-01

    In the future the air traffic will rise--the workload of the controllers will do the same. In the BMWi research project, one of the tasks is, how to ensure safe air traffic, and a reasonable workload for the air traffic controllers. In this project it was the goal to find ways how to reduce the workload (and stress) for the controllers to allow safe air traffic, esp. at huge hub-airports by implementing augmented reality visualization and interaction.

  15. Entropy, instrument scan and pilot workload

    NASA Technical Reports Server (NTRS)

    Tole, J. R.; Stephens, A. T.; Vivaudou, M.; Harris, R. L., Jr.; Ephrath, A. R.

    1982-01-01

    Correlation and information theory which analyze the relationships between mental loading and visual scanpath of aircraft pilots are described. The relationship between skill, performance, mental workload, and visual scanning behavior are investigated. The experimental method required pilots to maintain a general aviation flight simulator on a straight and level, constant sensitivity, Instrument Landing System (ILS) course with a low level of turbulence. An additional periodic verbal task whose difficulty increased with frequency was used to increment the subject's mental workload. The subject's looppoint on the instrument panel during each ten minute run was computed via a TV oculometer and stored. Several pilots ranging in skill from novices to test pilots took part in the experiment. Analysis of the periodicity of the subject's instrument scan was accomplished by means of correlation techniques. For skilled pilots, the autocorrelation of instrument/dwell times sequences showed the same periodicity as the verbal task. The ability to multiplex simultaneous tasks increases with skill. Thus autocorrelation provides a way of evaluating the operator's skill level.

  16. Visual scanning behavior and pilot workload

    NASA Technical Reports Server (NTRS)

    Tole, J. R.; Stephens, A. T.; Vivaudou, M.; Ephrath, A. R.; Young, L. R.

    1983-01-01

    Sophisticated man machine interaction often requires the human operator to perform a stereotyped scan of various instruments in order to monitor and/or control a system. For situations in which this type of stereotyped behavior exists, such as certain phases of instrument flight, scan pattern was shown to be altered by the imposition of simultaneous verbal tasks. A study designed to examine the relationship between pilot visual scan of instruments and mental workload is described. It was found that a verbal loading task of varying difficulty causes pilots to stare at the primary instrument as the difficulty increases and to shed looks at instruments of less importance. The verbal loading task also affected the rank ordering of scanning sequences. By examining the behavior of pilots with widely varying skill levels, it was suggested that these effects occur most strongly at lower skill levels and are less apparent at high skill levels. A graphical interpretation of the hypothetical relationship between skill, workload, and performance is introduced and modelling results are presented to support this interpretation.

  17. Physical workload and thoughts of retirement.

    PubMed

    Perkiö-Mäkelä, Merja; Hirvonen, Maria

    2012-01-01

    The aim of this paper is to present Finnish employees' opinions on continuing work until retirement pension and after the age of 63, and to find out if physical workload is related to these opinions. Altogether 39% of men and 40% of women had never had thoughts of early retirement, and 59% claimed (both men and women) that they would consider working beyond the age of 63. Own health (20%); financial gain such as salary and better pension (19%); meaningful, interesting and challenging work (15%); flexible working hours or part-time work (13%); lighter work load (13%); good work community (8%); and good work environment (6%) were stated as factors affecting the decision to continue working after the age of 63. Employees whose work involved low physical workload had less thoughts of early retirement and had considered continuing work after the age of 63 more often than those whose work involved high physical loads. Own health in particular was stated as a reason to consider continuing work by employees whose work was physically demanding.

  18. What's skill got to do with it? Vehicle automation and driver mental workload.

    PubMed

    Young, M S; Stanton, N A

    2007-08-01

    Previous research has found that vehicle automation systems can reduce driver mental workload, with implications for attentional resources that can be detrimental to performance. The present paper considers how the development of automaticity within the driving task may influence performance in underload situations. Driver skill and vehicle automation were manipulated in a driving simulator, with four levels of each variable. Mental workload was assessed using a secondary task measure and eye movements were recorded to infer attentional capacity. The effects of automation on driver mental workload were quite robust across skill levels, but the most intriguing findings were from the eye movement data. It was found that, with little exception, attentional capacity and mental workload were directly related at all levels of driver skill, consistent with earlier studies. The results are discussed with reference to applied theories of cognition and the design of automation.

  19. Stability and Workload of the Virtual Reality-Based Simulator-2.

    PubMed

    Kamaraj, Deepan C; Dicianno, Brad E; Mahajan, Harshal P; Buhari, Alhaji M; Cooper, Rory A

    2016-07-01

    To assess the stability of clinicians' and users' rating of electric-powered wheelchair (EPW) driving while using 4 different human-machine interfaces (HMIs) within the Virtual Reality-based SIMulator-version 2 (VRSIM-2) and in the real world (accounting for a total of 5 unique driving conditions). Within-subjects repeated-measures design. Simulation-based assessment in a research laboratory. A convenience sample of EPW athletes (N=21) recruited at the 31st National Veterans Wheelchair Games. Not applicable. Composite PMRT scores from the Power Mobility Road Test (PMRT); Raw Task Load Index; and the 6 subscale scores from the Task Load Index developed by the National Aeronautics and Space Administration (NASA-TLX). There was moderate stability (intraclass correlation coefficient between .50 and .75) in the total composite PMRT scores (P<.001) and the users' self-reported performance scores (P<.001) among the 5 driving conditions. There was a significant difference in the workload among the 5 different driving conditions as reflected by the Raw Task Load Index (P=.009). Subanalyses revealed this difference was due to the difference in the mental demand (P=.007) and frustration (P=.007) subscales. Post hoc analyses revealed that these differences in the NASA-TLX subscale scores were due to the differences between real-world and virtual driving scores, particularly attributable to the conditions (1 and 3) that lacked the rollers as a part of the simulation. Further design improvements in the simulator to increase immersion experienced by the EPW user, along with a standardized training program for clinicians to deliver PMRT in VRSIM-2, could improve the stability between the different HMIs and real-world driving. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  20. Mental workload and cognitive task automaticity: an evaluation of subjective and time estimation metrics.

    PubMed

    Liu, Y; Wickens, C D

    1994-11-01

    The evaluation of mental workload is becoming increasingly important in system design and analysis. The present study examined the structure and assessment of mental workload in performing decision and monitoring tasks by focusing on two mental workload measurements: subjective assessment and time estimation. The task required the assignment of a series of incoming customers to the shortest of three parallel service lines displayed on a computer monitor. The subject was either in charge of the customer assignment (manual mode) or was monitoring an automated system performing the same task (automatic mode). In both cases, the subjects were required to detect the non-optimal assignments that they or the computer had made. Time pressure was manipulated by the experimenter to create fast and slow conditions. The results revealed a multi-dimensional structure of mental workload and a multi-step process of subjective workload assessment. The results also indicated that subjective workload was more influenced by the subject's participatory mode than by the factor of task speed. The time estimation intervals produced while performing the decision and monitoring tasks had significantly greater length and larger variability than those produced while either performing no other tasks or performing a well practised customer assignment task. This result seemed to indicate that time estimation was sensitive to the presence of perceptual/cognitive demands, but not to response related activities to which behavioural automaticity has developed.

  1. Quantification of pilot workload via instrument scan

    NASA Technical Reports Server (NTRS)

    Tole, J. R.; Stephens, A. T.; Harris, R. L., Sr.; Ephrath, A.

    1982-01-01

    The use of visual scanning behavior as an indicator of pilot workload is described. The relationship between level of performance on a constant piloting task under simulated IFR conditions, the skill of the pilot the level of mental workload induced by an additional verbal task imposed on the basic control task, and visual scanning behavior is investigated. An increase in fixation dwell times, especially on the primary instrument with increased mental loading is indicated. Skilled subjects 'stared' less under increased loading than did novice pilots. Sequences of instrument fixations were also examined. The percentage occurrence of the subject's most used sequences decreased with increased task difficulty for novice subjects but not for highly skilled subjects. Entropy rate (bits/sec) of the sequence of fixations was also used to quantify the scan pattern. It consistently decreased for most subjects as the four loading levels used increased.

  2. Recruitment, Retention and the Workload Challenge: A Critique of the Government Response

    ERIC Educational Resources Information Center

    Quicke, John

    2018-01-01

    Various surveys have confirmed that there is a crisis of recruitment and retention of teachers in schools. This article examines the government response to this crisis, in particular to what is commonly cited as the main cause--unmanageable workloads. What it describes as the workload challenge has certainly not been ignored by the DfE, which in…

  3. Efficient mental workload estimation using task-independent EEG features.

    PubMed

    Roy, R N; Charbonnier, S; Campagne, A; Bonnet, S

    2016-04-01

    Mental workload is frequently estimated by EEG-based mental state monitoring systems. Usually, these systems use spectral markers and event-related potentials (ERPs). To our knowledge, no study has directly compared their performance for mental workload assessment, nor evaluated the stability in time of these markers and of the performance of the associated mental workload estimators.  This study proposes a comparison of two processing chains, one based on the power in five frequency bands, and one based on ERPs, both including a spatial filtering step (respectively CSP and CCA), an FLDA classification and a 10-fold cross-validation. To get closer to a real life implementation, spectral markers were extracted from a short window (i.e. towards reactive systems) that did not include any motor activity and the analyzed ERPs were elicited by a task-independent probe that required a reflex-like answer (i.e. close to the ones required by dead man's vigilance devices). The data were acquired from 20 participants who performed a Sternberg memory task for 90 min (i.e. 2/6 digits to memorize) inside which a simple detection task was inserted. The results were compared both when the testing was performed at the beginning and end of the session. Both chains performed significantly better than random; however the one based on the spectral markers had a low performance (60%) and was not stable in time. Conversely, the ERP-based chain gave very high results (91%) and was stable in time. This study demonstrates that an efficient and stable in time workload estimation can be achieved using task-independent spatially filtered ERPs elicited in a minimally intrusive manner.

  4. Efficient mental workload estimation using task-independent EEG features

    NASA Astrophysics Data System (ADS)

    Roy, R. N.; Charbonnier, S.; Campagne, A.; Bonnet, S.

    2016-04-01

    Objective. Mental workload is frequently estimated by EEG-based mental state monitoring systems. Usually, these systems use spectral markers and event-related potentials (ERPs). To our knowledge, no study has directly compared their performance for mental workload assessment, nor evaluated the stability in time of these markers and of the performance of the associated mental workload estimators. This study proposes a comparison of two processing chains, one based on the power in five frequency bands, and one based on ERPs, both including a spatial filtering step (respectively CSP and CCA), an FLDA classification and a 10-fold cross-validation. Approach. To get closer to a real life implementation, spectral markers were extracted from a short window (i.e. towards reactive systems) that did not include any motor activity and the analyzed ERPs were elicited by a task-independent probe that required a reflex-like answer (i.e. close to the ones required by dead man’s vigilance devices). The data were acquired from 20 participants who performed a Sternberg memory task for 90 min (i.e. 2/6 digits to memorize) inside which a simple detection task was inserted. The results were compared both when the testing was performed at the beginning and end of the session. Main results. Both chains performed significantly better than random; however the one based on the spectral markers had a low performance (60%) and was not stable in time. Conversely, the ERP-based chain gave very high results (91%) and was stable in time. Significance. This study demonstrates that an efficient and stable in time workload estimation can be achieved using task-independent spatially filtered ERPs elicited in a minimally intrusive manner.

  5. Estimating workload using EEG spectral power and ERPs in the n-back task

    NASA Astrophysics Data System (ADS)

    Brouwer, Anne-Marie; Hogervorst, Maarten A.; van Erp, Jan B. F.; Heffelaar, Tobias; Zimmerman, Patrick H.; Oostenveld, Robert

    2012-08-01

    Previous studies indicate that both electroencephalogram (EEG) spectral power (in particular the alpha and theta band) and event-related potentials (ERPs) (in particular the P300) can be used as a measure of mental work or memory load. We compare their ability to estimate workload level in a well-controlled task. In addition, we combine both types of measures in a single classification model to examine whether this results in higher classification accuracy than either one alone. Participants watched a sequence of visually presented letters and indicated whether or not the current letter was the same as the one (n instances) before. Workload was varied by varying n. We developed different classification models using ERP features, frequency power features or a combination (fusion). Training and testing of the models simulated an online workload estimation situation. All our ERP, power and fusion models provide classification accuracies between 80% and 90% when distinguishing between the highest and the lowest workload condition after 2 min. For 32 out of 35 participants, classification was significantly higher than chance level after 2.5 s (or one letter) as estimated by the fusion model. Differences between the models are rather small, though the fusion model performs better than the other models when only short data segments are available for estimating workload.

  6. The evaluation of team lifting on physical work demands and workload in ironworkers.

    PubMed

    van der Molen, Henk F; Visser, Steven; Kuijer, P Paul F M; Faber, Gert; Hoozemans, Marco J M; van Dieën, Jaap H; Frings-Dresen, Monique H W

    2012-01-01

    Lifting and carrying heavy loads occur frequently among ironworkers and result in high prevalence and incidence rates of low back complaints, injuries and work-disability. From a health perspective, little information is available on the effect of team lifting on work demands and workload. Therefore, the objective of this study was to compare the effects of team lifting of maximally 50 kg by two ironworkers (T50) with team lifting of maximally 100 kg by four ironworkers (T100). This study combined a field and laboratory study with the following outcome measures: duration and frequency of tasks and activities, energetic workload, perceived discomfort and maximal compression forces (Fc peak) on the low back. The physical work demands and workload of an individual iron worker during manual handling of rebar materials of 100 kg with four workers did not differ from the manual handling of rebar materials of 50 kg with two workers, with the exception of low back discomfort and Fc peak. The biomechanical workload of the low back exceeded for both T50 and T100 the NIOSH threshold limit of 3400N. Therefore, mechanical transport or other effective design solutions should be considered to reduce the biomechanical workload of the low back and the accompanying health risks among iron workers.

  7. Hysteresis in Mental Workload and Task Performance: The Influence of Demand Transitions and Task Prioritization.

    PubMed

    Jansen, Reinier J; Sawyer, Ben D; van Egmond, René; de Ridder, Huib; Hancock, Peter A

    2016-12-01

    We examine how transitions in task demand are manifested in mental workload and performance in a dual-task setting. Hysteresis has been defined as the ongoing influence of demand levels prior to a demand transition. Authors of previous studies predominantly examined hysteretic effects in terms of performance. However, little is known about the temporal development of hysteresis in mental workload. A simulated driving task was combined with an auditory memory task. Participants were instructed to prioritize driving or to prioritize both tasks equally. Three experimental conditions with low, high, and low task demands were constructed by manipulating the frequency of lane changing. Multiple measures of subjective mental workload were taken during experimental conditions. Contrary to our prediction, no hysteretic effects were found after the high- to low-demand transition. However, a hysteretic effect in mental workload was found within the high-demand condition, which degraded toward the end of the high condition. Priority instructions were not reflected in performance. Online assessment of both performance and mental workload demonstrates the transient nature of hysteretic effects. An explanation for the observed hysteretic effect in mental workload is offered in terms of effort regulation. An informed arrival at the scene is important in safety operations, but peaks in mental workload should be avoided to prevent buildup of fatigue. Therefore, communication technologies should incorporate the historical profile of task demand. © 2016, Human Factors and Ergonomics Society.

  8. Plasma irisin levels progressively increase in response to increasing exercise workloads in young, healthy, active subjects.

    PubMed

    Daskalopoulou, Stella S; Cooke, Alexandra B; Gomez, Yessica-Haydee; Mutter, Andrew F; Filippaios, Andreas; Mesfum, Ertirea T; Mantzoros, Christos S

    2014-09-01

    Irisin, a recently discovered myokine, has been shown to induce browning of white adipose tissue, enhancing energy expenditure and mediating some of the beneficial effects of exercise. We aimed to estimate the time frame of changes in irisin levels after acute exercise and the effect of different exercise workloads and intensities on circulating irisin levels immediately post-exercise. In a pilot study, four healthy subjects (22.5±1.7 years) underwent maximal workload exercise (maximal oxygen consumption, VO2 max) and blood was drawn at prespecified intervals to define the time frame of pre- and post-exercise irisin changes over a 24-h period. In the main study, 35 healthy, non-smoking (23.0±3.3 years) men and women (n=20/15) underwent three exercise protocols ≥48-h apart, in random order: i) maximal workload (VO2 max); ii) relative workload (70% of VO2 max/10 min); and iii) absolute workload (75 W/10 min). Blood was drawn immediately pre-exercise and 3 min post-exercise. In the pilot study, irisin levels increased by 35% 3 min post-exercise, then dropped and remained relatively constant. In the main study, irisin levels post-exercise were significantly higher than those of pre-exercise after all workloads (all, P<0.001). Post-to-pre-exercise differences in irisin levels were significantly different between workloads (P=0.001), with the greatest increase by 34% following maximal workload (P=0.004 vs relative and absolute). Circulating irisin levels were acutely elevated in response to exercise, with a greater increase after maximal workload. These findings suggest that irisin release could be a function of muscle energy demand. Future studies need to determine the underlying mechanisms of irisin release and explore irisin's therapeutic potential. © 2014 European Society of Endocrinology.

  9. K-12 Teachers' Preparedness for Utilizing Technology to Reduce Classroom Administrative Workload

    ERIC Educational Resources Information Center

    Parizo, Daniel C.

    2013-01-01

    Research on technology in the K-12 classroom has focused on student learning initiatives. Few studies, however, have addressed whether technology is being used to reduce classroom administrative workload or whether teachers are prepared to utilize technology for reducing administrative workload. The problem this study addressed was the unclear…

  10. Evaluation of Workload and its Impact on Satisfaction Among Pharmacy Academicians in Southern India.

    PubMed

    Ahmad, Akram; Khan, Muhammad Umair; Srikanth, Akshaya B; Patel, Isha; Nagappa, Anantha Naik; Jamshed, Shazia Qasim

    2015-06-01

    The purpose of this study was to determine the level of workload among pharmacy academicians working in public and private sector universities in India. The study also aimed to assess the satisfaction of academicians towards their workload. A cross-sectional study was conducted for a period of 2 months among pharmacy academicians in Karnataka state of Southern India. Convenience sampling was used to select a sample and was contacted via email and/or social networking sites. Questionnaire designed by thorough review literature was used as a tool to collect data on workload (teaching, research, extracurricular services) and satisfaction. Of 214 participants, 95 returned the filled questionnaire giving the response rate of 44.39%. Private sector academicians had more load of teaching (p=0.046) and they appeared to be less involved in research activities (p=0.046) as compared to public sector academicians. More than half of the respondents (57.9%) were satisfied with their workload with Assistant Professors were least satisfied as compared to Professors (p=0.01). Overall, private sector academicians are more burdened by teaching load and also are less satisfied of their workload. Revision of private universities policies may aid in addressing this issue.

  11. Progress in mental workload measurement

    NASA Technical Reports Server (NTRS)

    Moray, Neville; Turksen, Burhan; Aidie, Paul; Drascic, David; Eisen, Paul

    1986-01-01

    Two new techniques are described, one using subjective, the other physiological data for the measurement of workload in complex tasks. The subjective approach uses fuzzy measurement to analyze and predict the difficulty of combinations of skill based and rule based behavior from the difficulty of skill based behavior and rule based behavior measured separately. The physiological technique offers an on-line real-time filter for measuring the Mulder signal at 0.1 Hz in the heart rate variability spectrum.

  12. Bio-inspired diversity for increasing attacker workload

    NASA Astrophysics Data System (ADS)

    Kuhn, Stephen

    2014-05-01

    Much of the traffic in modern computer networks is conducted between clients and servers, rather than client-toclient. As a result, servers represent a high-value target for collection and analysis of network traffic. As they reside at a single network location (i.e. IP/MAC address) for long periods of time. Servers present a static target for surveillance, and a unique opportunity to observe the network traffic. Although servers present a heightened value for attackers, the security community as a whole has shifted more towards protecting clients in recent years leaving a gap in coverage. In addition, servers typically remain active on networks for years, potentially decades. This paper builds on previous work that demonstrated a proof of concept leveraging existing technology for increasing attacker workload. Here we present our clean slate approach to increasing attacker workload through a novel hypervisor and micro-kernel, utilizing next generation virtualization technology to create synthetic diversity of the server's presence including the hardware components.

  13. Use of the RoboFlag synthetic task environment to investigate workload and stress responses in UAV operation.

    PubMed

    Guznov, Svyatoslav; Matthews, Gerald; Funke, Gregory; Dukes, Allen

    2011-09-01

    Use of unmanned aerial vehicles (UAVs) is an increasingly important element of military missions. However, controlling UAVs may impose high stress and workload on the operator. This study evaluated the use of the RoboFlag simulated environment as a means for profiling multiple dimensions of stress and workload response to a task requiring control of multiple vehicles (robots). It tested the effects of two workload manipulations, environmental uncertainty (i.e., UAV's visual view area) and maneuverability, in 64 participants. The findings confirmed that the task produced substantial workload and elevated distress. Dissociations between the stress and performance effects of the manipulations confirmed the utility of a multivariate approach to assessment. Contrary to expectations, distress and some aspects of workload were highest in the low-uncertainty condition, suggesting that overload of information may be an issue for UAV interface designers. The strengths and limitations of RoboFlag as a methodology for investigating stress and workload responses are discussed.

  14. Multiplexing Low and High QoS Workloads in Virtual Environments

    NASA Astrophysics Data System (ADS)

    Verboven, Sam; Vanmechelen, Kurt; Broeckhove, Jan

    Virtualization technology has introduced new ways for managing IT infrastructure. The flexible deployment of applications through self-contained virtual machine images has removed the barriers for multiplexing, suspending and migrating applications with their entire execution environment, allowing for a more efficient use of the infrastructure. These developments have given rise to an important challenge regarding the optimal scheduling of virtual machine workloads. In this paper, we specifically address the VM scheduling problem in which workloads that require guaranteed levels of CPU performance are mixed with workloads that do not require such guarantees. We introduce a framework to analyze this scheduling problem and evaluate to what extent such mixed service delivery is beneficial for a provider of virtualized IT infrastructure. Traditionally providers offer IT resources under a guaranteed and fixed performance profile, which can lead to underutilization. The findings of our simulation study show that through proper tuning of a limited set of parameters, the proposed scheduling algorithm allows for a significant increase in utilization without sacrificing on performance dependability.

  15. Analysis of Mental Workload in Online Shopping: Are Augmented and Virtual Reality Consistent?

    PubMed

    Zhao, Xiaojun; Shi, Changxiu; You, Xuqun; Zong, Chenming

    2017-01-01

    A market research company (Nielsen) reported that consumers in the Asia-Pacific region have become the most active group in online shopping. Focusing on augmented reality (AR), which is one of three major techniques used to change the method of shopping in the future, this study used a mixed design to discuss the influences of the method of online shopping, user gender, cognitive style, product value, and sensory channel on mental workload in virtual reality (VR) and AR situations. The results showed that males' mental workloads were significantly higher than females'. For males, high-value products' mental workload was significantly higher than that of low-value products. In the VR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference was reduced under audio-visual conditions. In the AR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference increased under audio-visual conditions. This study provided a psychological study of online shopping with AR and VR technology with applications in the future. Based on the perspective of embodied cognition, AR online shopping may be potential focus of research and market application. For the future design of online shopping platforms and the updating of user experience, this study provides a reference.

  16. Analysis of Mental Workload in Online Shopping: Are Augmented and Virtual Reality Consistent?

    PubMed Central

    Zhao, Xiaojun; Shi, Changxiu; You, Xuqun; Zong, Chenming

    2017-01-01

    A market research company (Nielsen) reported that consumers in the Asia-Pacific region have become the most active group in online shopping. Focusing on augmented reality (AR), which is one of three major techniques used to change the method of shopping in the future, this study used a mixed design to discuss the influences of the method of online shopping, user gender, cognitive style, product value, and sensory channel on mental workload in virtual reality (VR) and AR situations. The results showed that males’ mental workloads were significantly higher than females’. For males, high-value products’ mental workload was significantly higher than that of low-value products. In the VR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference was reduced under audio–visual conditions. In the AR situation, the visual mental workload of field-independent and field-dependent consumers showed a significant difference, but the difference increased under audio–visual conditions. This study provided a psychological study of online shopping with AR and VR technology with applications in the future. Based on the perspective of embodied cognition, AR online shopping may be potential focus of research and market application. For the future design of online shopping platforms and the updating of user experience, this study provides a reference. PMID:28184207

  17. Synthesis of workload reduction strategies for construction inspection.

    DOT National Transportation Integrated Search

    2008-10-01

    State departments of transportation (DOTs) have seen significant funding increases throughout the past decade. The : additional funding has also brought about an increase in the construction inspection and testing workload, but the : DOTs have not se...

  18. EEG and ECG changes during simulator operation reflect mental workload and vigilance.

    PubMed

    Dussault, Caroline; Jouanin, Jean-Claude; Philippe, Matthieu; Guezennec, Charles-Yannick

    2005-04-01

    Performing mission tasks in a simulator influences many neurophysiological measures. Quantitative assessments of electroencephalography (EEG) and electrocardiography (ECG) have made it possible to develop indicators of mental workload and to estimate relative physiological responses to cognitive requirements. To evaluate the effects of mental workload without actual physical risk, we studied the cortical and cardiovascular changes that occurred during simulated flight. There were 12 pilots (8 novices and 4 experts) who simulated a flight composed of 10 sequences that induced several different mental workload levels. EEG was recorded at 12 electrode sites during rest and flight sequences; ECG activity was also recorded. Subjective tests were used to evaluate anxiety and vigilance levels. Theta band activity was lower during the two simulated flight rest sequences than during visual and instrument flight sequences at central, parietal, and occipital sites (p < 0.05). On the other hand, rest sequences resulted in higher beta (at the C4 site; p < 0.05) and gamma (at the central, parietal, and occipital sites; p < 0.05) power than active segments. The mean heart rate (HR) was not significantly different during any simulated flight sequence, but HR was lower for expert subjects than for novices. The subjective tests revealed no significant anxiety and high values for vigilance levels before and during flight. The different flight sequences performed on the simulator resulted in electrophysiological changes that expressed variations in mental workload. These results corroborate those found during study of real flights, particularly during sequences requiring the heaviest mental workload.

  19. Workload Influence on Fatigue Related Psychological and Physiological Performance Changes of Aviators

    PubMed Central

    Liu, Xi-Wen; Bian, Ka; Wen, Zhi-Hong; Li, Xiao-Jing; Zhang, Zuo-Ming; Hu, Wen-Dong

    2014-01-01

    Objective We evaluated a variety of non-invasive physiological technologies and a series of test approaches for examination of aviator performances under conditions of mental workload in order to provide a standard real-time test for physiological and psychological pilot fatigue assessments. Methods Twenty-one male aviators were selected for a simulated flight in a hypobaric cabin with artificial altitude conditions of 2400 meter above sea level. The simulated flight lasted for 1.5 h, and was repeated for two times with an intervening 0.5 h rest period outside the hypobaric cabin. Subjective criteria (a fatigue assessment instrument [FAI]) and objective criteria (a standing-position balance test as well as a critical flicker fusion frequency (CFF) test) were used for fatigue evaluations. Results No significant change was observed in the FAI scores before and after the simulated flight, indicating that there was no subjective fatigue feeling among the participants. However, significant differences were observed in the standing-position balance and CFF tests among the subjects, suggesting that psychophysiological indexes can reflect mental changes caused by workload to a certain extent. The CFF test was the simplest and clearly indicated the occurrence of workload influences on pilot performances after a simulated flight. Conclusions Results showed that the CFF test was the easiest way to detect workload caused mental changes after a simulated flight in a hypobaric cabin and reflected the psychophysiological state of aviators. We suggest that this test might be used as an effective routine method for evaluating the workload influences on mental conditions of aviators. PMID:24505277

  20. The smartphone and the driver's cognitive workload: A comparison of Apple, Google, and Microsoft's intelligent personal assistants.

    PubMed

    Strayer, David L; Cooper, Joel M; Turrill, Jonna; Coleman, James R; Hopman, Rachel J

    2017-06-01

    The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple's Siri , Google's Google Now for Android phones, and Microsoft's Cortana ) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive workload of drivers when they used the voice-based features of each smartphone to place a call, select music, or send text messages. Cognitive workload was derived from primary task performance through video analysis, secondary-task performance using the Detection Response Task (DRT), and subjective mental workload. We found that workload was significantly higher than that measured in the single-task drive. There were also systematic differences between the smartphones: The Google system placed lower cognitive demands on the driver than the Apple and Microsoft systems, which did not differ. Video analysis revealed that the difference in mental workload between the smartphones was associated with the number of system errors, the time to complete an action, and the complexity and intuitiveness of the devices. Finally, surprisingly high levels of cognitive workload were observed when drivers were interacting with the devices: "on-task" workload measures did not systematically differ from that associated with a mentally demanding Operation Span (OSPAN) task. The analysis also found residual costs associated using each of the smartphones that took a significant time to dissipate. The data suggest that caution is warranted in the use of smartphone voice-based technology in the vehicle because of the high levels of cognitive workload associated with these interactions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. [The measurement of nursing workload in a sub-intensive unit with the Nine Equivalents of Nursing Manpower Scale].

    PubMed

    D'Orazio, Alessia; Dragonetti, Antonella; Finiguerra, Ivana; Simone, Paola

    2015-01-01

    The measurement of nursing workload in a sub-intensive unit with the Nine Equivalents of Nursing Manpower Scale. The need to maximize the nursing manpower to patients complexity requires a careful assessment of the nursing workload. To measure the nursing workload in a sub-intensive care unit and to assess the impact of patients isolated for multidrug resistant microorganisms (MDR) and with delirium, on the nursing workload. From december 1 2014 to march 31 2015 the nursing workload of patients admitted to a semi intensive untit of a Turin Hospital was measured with Nine Equivalents of Nursing Manpower (NEMS) original and modified, adding 1 point score for patients isolated and with delirium (Richmond Agitation Sedation Scale). Admission and discharge times, and the activities performed in and out of the unit were registered. Two-hundred-thirty patients were daily assessed and no differences were observed in mean NEMS scores with the original and modified scale: december 17.3 vs 18.5; January 19.4 vs 20.2; February 19.9 vs 20.6; March 19.5 vs 20.1). mean scores did not change across shifts although on average 8 days a month the scores exceeded 21, identifiyng an excess workload and a need of a 2:1 patient/nurse ratio. The maximum workload was concentrated between 12.00 and 18.00 pm. The NEMS scale allows to measure the nursing workload. Apparently patients isolated and with delirium did not significantly impact on the nursing workload.

  2. Causes of dissociation between subjective workload measures and performance - Caveats for the use of subjective assessments

    NASA Technical Reports Server (NTRS)

    Vidulich, M. A.; Wickens, C. D.

    1985-01-01

    Dissociations between subjective workload assessments and performance were investigated. The difficulty of a Sternberg memory search task was manipulated by varying stimulus presentation rate, stimulus discernibility, value of good performance, and automaticity of performance. All Sternberg task conditions were performed both alone and concurrently with a tracking task. Bipolar subjective workload assessments were collected. Dissociations between workload and performance were found related to automaticity, presentation rate, and motivation level. The results were interpreted as supporting the hypothesis that the specific cognitive processes responsible for subjective assessments can differ from those responsible for performance. The potential contamination these dissociations could inflict on operational workload assessments is discussed.

  3. Interaction between workload and training - Converging evidence from psychophysiology and performance measurement

    NASA Technical Reports Server (NTRS)

    Kramer, Arthur F.

    1986-01-01

    Traditionally, the domains of mental workload and training have been studied in isolation even though they share many common characteristics. The present paper integrates findings from psychophysiological and performance-based studies which address both of these issues. By augmenting traditional indices of skill acquisition such as RMS error scores, reaction times, and accuracy measures with psychophysiological measures such as the event-related brain potential, it is shown that workload effects can be assessed throughout the training process. More specifically, it is argued that the development of skill and the effects of workload on the human operator can be modeled within the framework of resource theories of attentional allocation. Also described is how converging evidence from psychophysiological and behavioral studies can be used to examine subtle changes in operator strategies during training.

  4. Electromagnetic Metrics of Mental Workload.

    DTIC Science & Technology

    1987-09-01

    anxiety ). A decrease in performance accuracy has been used in the context of over- load, however it has also been associated with a "high workload". 1.2...heart rate variability ( HRV ) to refer to any varia- tion from a constant heart rate. The term HRV shall not refer to any specific method of numerically...in using HRV as a measure of mental load arose after Kalsbeek & Ettema (1963) reported that HRV was "gradu- ally suppressed when increasing the

  5. The most economical cadence increases with increasing workload.

    PubMed

    Foss, Øivind; Hallén, Jostein

    2004-08-01

    Several studies have suggested that the most economical cadence in cycling increases with increasing workload. However, none of these studies have been able to demonstrate this relationship with experimental data. The purpose of this study was to test the hypothesis that the most economical cadence in elite cyclists increases with increasing workload and to explore the effect of cadence on performance. Six elite road cyclists performed submaximal and maximal tests at four different cadences (60, 80, 100 and 120 rpm) on separate days. Respiratory data was measured at 0, 50, 125, 200, 275 and 350 W during the submaximal test and at the end of the maximal test. The maximal test was carried out as an incremental test, conducted to reveal differences in maximal oxygen uptake and time to exhaustion (short-term performance) between cadences. The results showed that the lowest oxygen uptake, i.e. the best work economy, shifted from 60 rpm at 0 W to 80 rpm at 350 W ( P<0.05). No difference was found in maximal oxygen uptake among cadences ( P>0.05), while the best performance was attained at the same cadence that elicited the best work economy (80 rpm) at 350 W ( P<0.05). This study demonstrated that the most economical cadence increases with increasing workload in elite cyclists. It was further shown that work economy and performance are related during short efforts (approximately 5 min) over a wide range of cadences.

  6. Determining Nurse Aide Staffing Requirements to Provide Care Based on Resident Workload: A Discrete Event Simulation Model.

    PubMed

    Schnelle, John F; Schroyer, L Dale; Saraf, Avantika A; Simmons, Sandra F

    2016-11-01

    Nursing aides provide most of the labor-intensive activities of daily living (ADL) care to nursing home (NH) residents. Currently, most NHs do not determine nurse aide staffing requirements based on the time to provide ADL care for their unique resident population. The lack of an objective method to determine nurse aide staffing requirements suggests that many NHs could be understaffed in their capacity to provide consistent ADL care to all residents in need. Discrete event simulation (DES) mathematically models key work parameters (eg, time to provide an episode of care and available staff) to predict the ability of the work setting to provide care over time and offers an objective method to determine nurse aide staffing needs in NHs. This study had 2 primary objectives: (1) to describe the relationship between ADL workload and the level of nurse aide staffing reported by NHs; and, (2) to use a DES model to determine the relationship between ADL workload and nurse aide staffing necessary for consistent, timely ADL care. Minimum Data Set data related to the level of dependency on staff for ADL care for residents in over 13,500 NHs nationwide were converted into 7 workload categories that captured 98% of all residents. In addition, data related to the time to provide care for the ADLs within each workload category was used to calculate a workload score for each facility. The correlation between workload and reported nurse aide staffing levels was calculated to determine the association between staffing reported by NHs and workload. Simulations to project staffing requirements necessary to provide ADL care were then conducted for 65 different workload scenarios, which included 13 different nurse aide staffing levels (ranging from 1.6 to 4.0 total hours per resident day) and 5 different workload percentiles (ranging from the 5th to the 95th percentile). The purpose of the simulation model was to determine the staffing necessary to provide care within each workload

  7. On the measurement of pilot perceptual workload - A comparison of assessment techniques addressing sensitivity and intrusion issues

    NASA Technical Reports Server (NTRS)

    Casali, J. G.; Wierwille, W. W.

    1984-01-01

    A flight simulator-based study was conducted to examine fourteen distinct mental workload estimation measures, including opinion, secondary task, physiological, and primary task measures. Both the relative sensitivity of the measures to changes in mental workload and the differential intrusion of the changes on primary task performance were assessed. The flight task was varied in difficulty by manipulation of the presentation rate and complexity of a hazard-perception task that required each of 48 licensed pilots to rely heavily on their perceptual abilities. Three rating scales (Modified Cooper-Harper, Multi-descriptor, and Workload-Compensation-Interference/Technical Effectiveness), two secondary task measures (time estimation and tapping regularity), one physiological measure (respiration frequency), and one primary task measure (danger-condition response time) were reliable indicants of workload changes. Recommendations for applying the workload measures are presented.

  8. An Investigation of the Workload and Job Satisfaction of North Carolina's Special Education Directors

    ERIC Educational Resources Information Center

    Cash, Jennifer Brown

    2013-01-01

    Keywords: special education directors, workload, job satisfaction, special education administration. The purpose of this mixed methods research study was to investigate employee characteristics, workload, and job satisfaction of special education directors employed by local education agencies in North Carolina (N = 115). This study illuminates the…

  9. Heart Rate Variability as a Measure of Airport Ramp-Traffic Controllers Workload

    NASA Technical Reports Server (NTRS)

    Hayashi, Miwa; Dulchinos, Victoria Lee

    2016-01-01

    Heart Rate Variability (HRV) has been reported to reflect the person's cognitive and emotional stress levels, and may offer an objective measure of human-operator's workload levels, which are recorded continuously and unobtrusively to the task performance. The present paper compares the HRV data collected during a human-in-the-loop simulation of airport ramp-traffic control operations with the controller participants' own verbal self-reporting ratings of their workload.

  10. Training loads and injury risk in Australian football—differing acute: chronic workload ratios influence match injury risk

    PubMed Central

    Carey, David L; Blanch, Peter; Ong, Kok-Leong; Crossley, Kay M; Crow, Justin; Morris, Meg E

    2017-01-01

    Aims (1) To investigate whether a daily acute:chronic workload ratio informs injury risk in Australian football players; (2) to identify which combination of workload variable, acute and chronic time window best explains injury likelihood. Methods Workload and injury data were collected from 53 athletes over 2 seasons in a professional Australian football club. Acute:chronic workload ratios were calculated daily for each athlete, and modelled against non-contact injury likelihood using a quadratic relationship. 6 workload variables, 8 acute time windows (2–9 days) and 7 chronic time windows (14–35 days) were considered (336 combinations). Each parameter combination was compared for injury likelihood fit (using R2). Results The ratio of moderate speed running workload (18–24 km/h) in the previous 3 days (acute time window) compared with the previous 21 days (chronic time window) best explained the injury likelihood in matches (R2=0.79) and in the immediate 2 or 5 days following matches (R2=0.76–0.82). The 3:21 acute:chronic workload ratio discriminated between high-risk and low-risk athletes (relative risk=1.98–2.43). Using the previous 6 days to calculate the acute workload time window yielded similar results. The choice of acute time window significantly influenced model performance and appeared to reflect the competition and training schedule. Conclusions Daily workload ratios can inform injury risk in Australian football. Clinicians and conditioning coaches should consider the sport-specific schedule of competition and training when choosing acute and chronic time windows. For Australian football, the ratio of moderate speed running in a 3-day or 6-day acute time window and a 21-day chronic time window best explained injury risk. PMID:27789430

  11. Evaluation of Workload and its Impact on Satisfaction Among Pharmacy Academicians in Southern India

    PubMed Central

    Khan, Muhammad Umair; Srikanth, Akshaya B.; Patel, Isha; Nagappa, Anantha Naik; Jamshed, Shazia Qasim

    2015-01-01

    Objective The purpose of this study was to determine the level of workload among pharmacy academicians working in public and private sector universities in India. The study also aimed to assess the satisfaction of academicians towards their workload. Materials and Methods A cross-sectional study was conducted for a period of 2 months among pharmacy academicians in Karnataka state of Southern India. Convenience sampling was used to select a sample and was contacted via email and/or social networking sites. Questionnaire designed by thorough review literature was used as a tool to collect data on workload (teaching, research, extracurricular services) and satisfaction. Results Of 214 participants, 95 returned the filled questionnaire giving the response rate of 44.39%. Private sector academicians had more load of teaching (p=0.046) and they appeared to be less involved in research activities (p=0.046) as compared to public sector academicians. More than half of the respondents (57.9%) were satisfied with their workload with Assistant Professors were least satisfied as compared to Professors (p=0.01). Conclusion Overall, private sector academicians are more burdened by teaching load and also are less satisfied of their workload. Revision of private universities policies may aid in addressing this issue. PMID:26266133

  12. Dynamics of Perceived Exertion in Constant-Power Cycling: Time- and Workload-Dependent Thresholds

    ERIC Educational Resources Information Center

    Balagué, Natàlia; Hristovski, Robert; García, Sergi; Aguirre, Cecilia; Vázquez, Pablo; Razon, Selen; Tenenbaum, Gershon

    2015-01-01

    Purpose: The purpose of this study was to test the dynamics of perceived exertion shifts (PES) as a function of time and workload during constant-power cycling. Method: Fifty-two participants assigned to 4 groups performed a cycling task at 4 different constant workloads corresponding to their individual rates of perceived exertion (RPEs = 13, 15,…

  13. Validation of Variations in Mental Workload as a Function of Scenario Difficulty: Traffic Density and Visibility

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Fluctuations in mental workload can be expected as a function of traffic density and visibility. The aim of the current investigation was to establish simulation scenarios that differed in attentional processing requirements. Four scenarios were created and tested representing two levels of traffic density (urban versus freeway) and two levels of visibility (clear versus foggy). An array of mental workload assessment measures were used to exam changes in attentional processing requirements in each scenario. The assessment array consisted of physiological (P300 amplitude and latency) and behavioral (RT and accuracy) indices. Preliminary results indicate that workload differs significantly as a function of traffic density in rural versus freeway scenarios. Workload also differs significantly in rural versus freeway scenarios as a function of visibility as observed by a significant interaction between the two variables of interest. Results are discussed in terms of their application for validating the difficulty level of simulation scenarios as a format for examining mental workload.

  14. Subjective health complaints and self-rated health: are expectancies more important than socioeconomic status and workload?

    PubMed

    Ree, Eline; Odeen, Magnus; Eriksen, Hege R; Indahl, Aage; Ihlebæk, Camilla; Hetland, Jørn; Harris, Anette

    2014-06-01

    The associations between socioeconomic status (SES), physical and psychosocial workload and health are well documented. According to The Cognitive Activation Theory of Stress (CATS), learned response outcome expectancies (coping, helplessness, and hopelessness) are also important contributors to health. This is in part as independent factors for health, but coping may also function as a buffer against the impact different demands have on health. The purpose of this study was to investigate the relative effect of SES (as measured by level of education), physical workload, and response outcome expectancies on subjective health complaints (SHC) and self-rated health, and if response outcome expectancies mediate the effects of education and physical workload on SHC and self-rated health. A survey was carried out among 1,746 Norwegian municipal employees (mean age 44.2, 81 % females). Structural Equation Models with SHC and self-rated health as outcomes were conducted. Education, physical workload, and response outcome expectancies, were the independent 28 variables in the model. Helplessness/hopelessness had a stronger direct effect on self-rated health and SHC than education and physical workload, for both men and women. Helplessness/hopelessness fully mediated the effect of physical workload on SHC for men (0.121), and mediated 30 % of a total effect of 0.247 for women. For women, education had a small but significant indirect effect through helplessness/hopelessness on self-rated health (0.040) and SHC (-0.040), but no direct effects were found. For men, there was no effect of education on SHC, and only a direct effect on self-rated health (0.134). The results indicated that helplessness/hopelessness is more important for SHC and health than well-established measures on SES such as years of education and perceived physical workload in this sample. Helplessness/hopelessness seems to function as a mechanism between physical workload and health.

  15. Service and Education: The Association Between Workload, Patient Complexity, and Teaching on Internal Medicine Inpatient Services.

    PubMed

    Ratcliffe, Temple A; Crabtree, Meghan A; Palmer, Raymond F; Pugh, Jacqueline A; Lanham, Holly J; Leykum, Luci K

    2018-04-01

    Attending rounds remain the primary venue for formal teaching and learning at academic medical centers. Little is known about the effect of increasing clinical demands on teaching during attending rounds. To explore the relationships among teaching time, teaching topics, clinical workload, and patient complexity variables. Observational study of medicine teaching teams from September 2008 through August 2014. Teams at two large teaching hospitals associated with a single medical school were observed for periods of 2 to 4 weeks. Twelve medicine teaching teams consisting of one attending, one second- or third-year resident, two to three interns, and two to three medical students. The study examined relationships between patient complexity (comorbidities, complications) and clinical workload variables (census, turnover) with educational measures. Teams were clustered based on clinical workload and patient complexity. Educational measures of interest were time spent teaching and number of teaching topics. Data were analyzed both at the daily observation level and across a given patient's admission. We observed 12 teams, 1994 discussions (approximately 373 h of rounds) of 563 patients over 244 observation days. Teams clustered into three groups: low patient complexity/high clinical workload, average patient complexity/low clinical workload, and high patient complexity/high clinical workload. Modest associations for team, patient complexity, and clinical workload variables were noted with total time spent teaching (9.1% of the variance in time spent teaching during a patient's admission; F[8,549] = 6.90, p < 0.001) and number of teaching topics (16% of the variance in the total number of teaching topics during a patient's admission; F[8,548] = 14.18, p < 0.001). Clinical workload and patient complexity characteristics among teams were only modestly associated with total teaching time and teaching topics.

  16. Input Device Characteristics Contribute to Performance during Training to Operate a Simulated Micro-Unmanned Aerial Vehicle

    DTIC Science & Technology

    2010-10-01

    mission, participants were given the NASA Task Load Index ( NASA TLX ) to measure subjective workload. Additional performance measures included mission...16 NASA TLX Workload Analyses...worksheet (See Appendix C), the Hidden Patterns Test (ETS, 1976), and an electronic form of the NASA Task Load Index ( TLX ; Hart & Staveland, 1988). The

  17. Faculty Workload Issues Connected to Undergraduate Research

    ERIC Educational Resources Information Center

    Free, Rhona; Griffith, Suzanne; Spellman, Bill

    2015-01-01

    This chapter delineates the consortial activities of the Council of Public Liberal Arts Colleges (COPLAC) to explore models of undergraduate research and to address the impact of undergraduate research on faculty workload. The significant progress made on the member campus of the University of Wisconsin-Superior over the last 10 years is…

  18. Objective methods for developing indices of pilot workload.

    DOT National Transportation Integrated Search

    1977-07-01

    This paper discusses the various types of objective methodologies that either have been or have the potential of being applied to the general problem of the measurement of pilot workload as it occurs on relatively short missions or mission phases. Se...

  19. Allocation of Academic Workloads in the Faculty of Human and Social Sciences at a South African University

    ERIC Educational Resources Information Center

    Botha, P. A.; Swanepoel, S.

    2015-01-01

    This article reports on the results of a statistical analysis of the weekly working hours of academics in a Faculty of Human and Social Sciences at a South African university. The aim was to quantify, analyse and compare the workload of academic staff. Seventy-five academics self-reported on their workload by completing the workload measuring…

  20. Using theta and alpha band power to assess cognitive workload in multitasking environments.

    PubMed

    Puma, Sébastien; Matton, Nadine; Paubel, Pierre-V; Raufaste, Éric; El-Yagoubi, Radouane

    2018-01-01

    Cognitive workload is of central importance in the fields of human factors and ergonomics. A reliable measurement of cognitive workload could allow for improvements in human machine interface designs and increase safety in several domains. At present, numerous studies have used electroencephalography (EEG) to assess cognitive workload, reporting the rise in cognitive workload to be associated with increases in theta band power and decreases in alpha band power. However, results have been inconsistent with some failing to reach the required level of significance. We hypothesized that the lack of consistency could be related to individual differences in task performance and/or to the small sample sizes in most EEG studies. In the present study we used EEG to assess the increase in cognitive workload occurring in a multitasking environment while taking into account differences in performance. Twenty participants completed a task commonly used in airline pilot recruitment, which included an increasing number of concurrent sub-tasks to be processed from one to four. Subjective ratings, performances scores, pupil size and EEG signals were recorded. Results showed that increases in EEG alpha and theta band power reflected increases in the involvement of cognitive resources for the completion of one to three subtasks in a multitasking environment. These values reached a ceiling when performances dropped. Consistent differences in levels of alpha and theta band power were associated to levels of task performance: highest performance was related to lowest band power. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. A simulation study on the constancy of cardiac energy metabolites during workload transition.

    PubMed

    Saito, Ryuta; Takeuchi, Ayako; Himeno, Yukiko; Inagaki, Nobuya; Matsuoka, Satoshi

    2016-12-01

    The cardiac energy metabolites such as ATP, phosphocreatine, ADP and NADH are kept relatively constant during physiological cardiac workload transition. How this is accomplished is not yet clarified, though Ca 2+ has been suggested to be one of the possible mechanisms. We constructed a detailed mathematical model of cardiac mitochondria based on experimental data and studied whether known Ca 2+ -dependent regulation mechanisms play roles in the metabolite constancy. Model simulations revealed that the Ca 2+ -dependent regulation mechanisms have important roles under the in vitro condition of isolated mitochondria where malate and glutamate were mitochondrial substrates, while they have only a minor role and the composition of substrates has marked influence on the metabolite constancy during workload transition under the simulated in vivo condition where many substrates exist. These results help us understand the regulation mechanisms of cardiac energy metabolism during physiological cardiac workload transition. The cardiac energy metabolites such as ATP, phosphocreatine, ADP and NADH are kept relatively constant over a wide range of cardiac workload, though the mechanisms are not yet clarified. One possible regulator of mitochondrial metabolism is Ca 2+ , because it activates several mitochondrial enzymes and transporters. Here we constructed a mathematical model of cardiac mitochondria, including oxidative phosphorylation, substrate metabolism and ion/substrate transporters, based on experimental data, and studied whether the Ca 2+ -dependent activation mechanisms play roles in metabolite constancy. Under the in vitro condition of isolated mitochondria, where malate and glutamate were used as mitochondrial substrates, the model well reproduced the Ca 2+ and inorganic phosphate (P i ) dependences of oxygen consumption, NADH level and mitochondrial membrane potential. The Ca 2+ -dependent activations of the aspartate/glutamate carrier and the F 1 F o -ATPase, and

  2. Analytic and subjective assessments of operator workload imposed by communications tasks in transport aircraft

    NASA Technical Reports Server (NTRS)

    Eckel, J. S.; Crabtree, M. S.

    1984-01-01

    Analytical and subjective techniques that are sensitive to the information transmission and processing requirements of individual communications-related tasks are used to assess workload imposed on the aircrew by A-10 communications requirements for civilian transport category aircraft. Communications-related tasks are defined to consist of the verbal exchanges between crews and controllers. Three workload estimating techniques are proposed. The first, an information theoretic analysis, is used to calculate bit values for perceptual, manual, and verbal demands in each communication task. The second, a paired-comparisons technique, obtains subjective estimates of the information processing and memory requirements for specific messages. By combining the results of the first two techniques, a hybrid analytical scale is created. The third, a subjective rank ordering of sequences of communications tasks, provides an overall scaling of communications workload. Recommendations for future research include an examination of communications-induced workload among the air crew and the development of simulation scenarios.

  3. Analysis of the workload of bank tellers of a Brazilian public institution.

    PubMed

    Serikawa, Simoni S; Albieri, Ana Carolina S; Bonugli, Gustavo P; Greghi, Marina F

    2012-01-01

    During the last decades there have been many changes in the banking sector organization. It has been also observed the mutual growing of musculoskeletal and mental disorders. This study investigated the workload of bank tellers at a Brazilian public institution. It was performed the Ergonomic Work Analysis (EWA). Three employees participated in this study. During the analysis process, three research instruments were applied: Inventory of Work and Risk of Illness, Yoshitake Fatigue Questionnaire and Nordic Musculoskeletal Questionnaire, beyond the realization of footage recordings and the self-confrontation. The results indicated the existence of an excess of workload on the evaluated workstations, mainly in relation to mental order constraints, that overlaps the physical aspects. Thereby it was found that the employees tend to adopt strategies trying to reduce the impacts of the excess of workload, in order to regulate it.

  4. Evolutionary Multiobjective Query Workload Optimization of Cloud Data Warehouses

    PubMed Central

    Dokeroglu, Tansel; Sert, Seyyit Alper; Cinar, Muhammet Serkan

    2014-01-01

    With the advent of Cloud databases, query optimizers need to find paretooptimal solutions in terms of response time and monetary cost. Our novel approach minimizes both objectives by deploying alternative virtual resources and query plans making use of the virtual resource elasticity of the Cloud. We propose an exact multiobjective branch-and-bound and a robust multiobjective genetic algorithm for the optimization of distributed data warehouse query workloads on the Cloud. In order to investigate the effectiveness of our approach, we incorporate the devised algorithms into a prototype system. Finally, through several experiments that we have conducted with different workloads and virtual resource configurations, we conclude remarkable findings of alternative deployments as well as the advantages and disadvantages of the multiobjective algorithms we propose. PMID:24892048

  5. Assessment of mental workload and academic motivation in medical students.

    PubMed

    Atalay, Kumru Didem; Can, Gulin Feryal; Erdem, Saban Remzi; Muderrisoglu, Ibrahim Haldun

    2016-05-01

    To investigate the level of correlation and direction of linearity between academic motivation and subjective workload. The study was conducted at Baskent University School of Medicine, Ankara, Turkey, from December 2013 to February 2014, and comprised Phase 5 Phase 6 medical students. Subjective workload level was determined by using National Aeronautics and Space Administration Task Load Index scale that was adapted to Turkish. Academic motivation values were obtained with the help of Academic Motivation Scale university form. SPSS 17 was used for statistical analysis. Of the total 105 subjects, 65(62%) students were in Phase 5 and 40(38%) were in Phase 6. Of the Phase 5 students, 18(27.7%) were boys and 47(72.3%) were girls, while of the Phase 6 students, 16(40%) were boys and 24(60%) were girls. There were significant differences in Phase 5 and Phase 6 students for mental effort (p=0.00) and physical effort (p=0.00). The highest correlation in Phase 5 was between mental effort and intrinsic motivation (r=0.343). For Phase 6, highest correlation was between effort and amotivation (r= -0.375). Subjective workload affected academic motivation in medical students.

  6. Work-Based Social Interactions, Perceived Stress, and Workload Incongruence as Antecedents of Athletic Trainer Burnout.

    PubMed

    DeFreese, J D; Mihalik, Jason P

    2016-01-01

    Burnout is an important psychological health concern for working professionals. Understanding how psychological stress and markers of workload contribute to athletic trainers' (ATs') perceptions of burnout is highly valuable. Both positive (social support) and negative social interactions should be considered when examining relationships among markers of ATs' health and wellbeing. To examine the potential effects of social interactions on the relationships between (1) burnout and perceived stress and (2) burnout and workload incongruence in ATs. Cross-sectional study. Participating ATs completed a computer-based survey during the fall sports season. Responding participants were ATs randomly sampled from the National Athletic Trainers' Association membership (N = 154; men = 78, women = 76; age = 36.8 ± 9.5 years). Participants completed self-report assessments (Perceived Stress Scale, Social Support Questionnaire, Positive and Negative Social Exchanges, Maslach Burnout Inventory-Human Services Survey) via a secure e-mail link. Workload incongruence was calculated by subtracting anticipated work hours from actual current work hours (6.0 ± 9.6 hours). We used hierarchical multiple regression analyses to examine hypothesized relationships among study variables. Social interactions did not affect the relationships between burnout and perceived stress or workload incongruence at the global or dimensional level. However, perceived stress (β = .47, P < .001), workload incongruence (β = .12, P < .05), and social support (β = -.25, P < .001) predicted global AT burnout. Negative social interactions trended toward significance (β = .12, P = .055). Our findings suggest that stress perceptions and social support drive the dimensional AT burnout experience, whereas workload incongruence (emotional exhaustion) and negative social interactions (depersonalization) were linked to specific burnout dimensions. Social interactions and markers of stress and workload should be

  7. Work-Based Social Interactions, Perceived Stress, and Workload Incongruence as Antecedents of Athletic Trainer Burnout

    PubMed Central

    DeFreese, J. D.; Mihalik, Jason P.

    2016-01-01

    Context Burnout is an important psychological health concern for working professionals. Understanding how psychological stress and markers of workload contribute to athletic trainers' (ATs') perceptions of burnout is highly valuable. Both positive (social support) and negative social interactions should be considered when examining relationships among markers of ATs' health and wellbeing. Objective To examine the potential effects of social interactions on the relationships between (1) burnout and perceived stress and (2) burnout and workload incongruence in ATs. Design Cross-sectional study. Setting Participating ATs completed a computer-based survey during the fall sports season. Patients or Other Participants Responding participants were ATs randomly sampled from the National Athletic Trainers' Association membership (N = 154; men = 78, women = 76; age = 36.8 ± 9.5 years). Main Outcome Measure(s) Participants completed self-report assessments (Perceived Stress Scale, Social Support Questionnaire, Positive and Negative Social Exchanges, Maslach Burnout Inventory–Human Services Survey) via a secure e-mail link. Workload incongruence was calculated by subtracting anticipated work hours from actual current work hours (6.0 ± 9.6 hours). We used hierarchical multiple regression analyses to examine hypothesized relationships among study variables. Results Social interactions did not affect the relationships between burnout and perceived stress or workload incongruence at the global or dimensional level. However, perceived stress (β = .47, P < .001), workload incongruence (β = .12, P < .05), and social support (β = −.25, P < .001) predicted global AT burnout. Negative social interactions trended toward significance (β = .12, P = .055). Our findings suggest that stress perceptions and social support drive the dimensional AT burnout experience, whereas workload incongruence (emotional exhaustion) and negative social interactions (depersonalization) were linked

  8. Quantification of crew workload imposed by communications-related tasks in commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    Acton, W. H.; Crabtree, M. S.; Simons, J. C.; Gomer, F. E.; Eckel, J. S.

    1983-01-01

    Information theoretic analysis and subjective paired-comparison and task ranking techniques were employed in order to scale the workload of 20 communications-related tasks frequently performed by the captain and first officer of transport category aircraft. Tasks were drawn from taped conversations between aircraft and air traffic controllers (ATC). Twenty crewmembers performed subjective message comparisons and task rankings on the basis of workload. Information theoretic results indicated a broad range of task difficulty levels, and substantial differences between captain and first officer workload levels. Preliminary subjective data tended to corroborate these results. A hybrid scale reflecting the results of both the analytical and the subjective techniques is currently being developed. The findings will be used to select representative sets of communications for use in high fidelity simulation.

  9. Is This Work Sustainable? Teacher Turnover and Perceptions of Workload in Charter Management Organizations

    ERIC Educational Resources Information Center

    Torres, A. Chris

    2016-01-01

    An unsustainable workload is considered the primary cause of teacher turnover at Charter Management Organizations (CMOs), yet most reports provide anecdotal evidence to support this claim. This study uses 2010-2011 survey data from one large CMO and finds that teachers' perceptions of workload are significantly associated with decisions to leave…

  10. Health impairment of system engineers working on projects with heavy workload.

    PubMed

    Shimizui, Hayato; Ooshima, Kirika; Miki, Akiko; Matsushita, Yoshie; Hattori, Youji; Sugita, Minoru

    2011-03-01

    It has been reported that many system engineers must work hard to produce computer systems, and some of them suffer from health impairment due to their hard work. The purpose of the present cross-sectional study was to investigate the situation of impaired health status of system engineers in projects with high job strain. Countermeasures against health impairment of the subjects in the projects with high job strain in practices of occupational health fields are discussed. The study subjects were five superiors and their 35 subordinates working on computer system projects with high job strain at a large computer systems corporation in the Tokyo area. The control group was comprised of three superiors and their 18 subordinates in the same corporation. From July to November, 2006, the above were interviewed by six occupational health nurses, who evaluated their health and recorded their health evaluation scores. The problems involved in producing the computer systems were sometimes very difficult to solve, even if they spent long hours working on them. The present study detected a tendency showing that healthy superiors' subordinates were unhealthy and unhealthy superiors' subordinates were healthy in the overload projects with high job strain, while this was not detected in the control groups. A few employees whose health deteriorated were faced with very hard jobs in the overload projects. This means that heavy workloads were unevenly distributed in the overload projects among superiors, and their subordinates, and the health of a few members with heavy workloads deteriorated due to the heavy workload. In order to improve such a situation, it may be important not only to commit the necessary number of employees whose working ability is high to the section but also to even the workload in the overload project by informing all members of the project the health impairment of a few members due to heavy workload, from the viewpoint of the practice of occupational health

  11. Effect of block weight on work demands and physical workload during masonry work.

    PubMed

    Van Der Molen, H F; Kuijer, P P F M; Hopmans, P P W; Houweling, A G; Faber, G S; Hoozemans, M J M; Frings-Dresen, M H W

    2008-03-01

    The effect of block weight on work demands and physical workload was determined for masons who laid sandstone building blocks over the course of a full work day. Three groups of five sandstone block masons participated. Each group worked with a different block weight: 11 kg, 14 kg or 16 kg. Productivity and durations of tasks and activities were assessed through real time observations at the work site. Energetic workload was also assessed through monitoring the heart rate and oxygen consumption at the work site. Spinal load of the low back was estimated by calculating the cumulated elastic energy stored in the lumbar spine using durations of activities and previous data on corresponding compression forces. Block weight had no effect on productivity, duration or frequency of tasks and activities, energetic workload or cumulative spinal load. Working with any of the block weights exceeded exposure guidelines for work demands and physical workload. This implies that, regardless of block weight in the range of 11 to 16 kg, mechanical lifting equipment or devices to adjust work height should be implemented to substantially lower the risk of low back injuries.

  12. Measuring workload for tuberculosis service provision at primary care level: a methodology

    PubMed Central

    2012-01-01

    We developed and piloted a methodology to establish TB related work load at primary care level for clinical and laboratory staff. Workload is influenced by activities to be implemented, time to perform them, their frequency and patient load. Of particular importance is the patient pathway for diagnosis and treatment and the frequency of clinic visits. Using observation with checklists, clocking, interviews and review of registers, allows assessing the contribution of different factors on the workload. PMID:22640406

  13. Principal Workload: Components, Determinants and Coping Strategies in an Era of Standardization and Accountability

    ERIC Educational Resources Information Center

    Oplatka, Izhar

    2017-01-01

    Purpose: In order to fill the gap in theoretical and empirical knowledge about the characteristics of principal workload, the purpose of this paper is to explore the components of principal workload as well as its determinants and the coping strategies commonly used by principals to face this personal state. Design/methodology/approach:…

  14. Training loads and injury risk in Australian football-differing acute: chronic workload ratios influence match injury risk.

    PubMed

    Carey, David L; Blanch, Peter; Ong, Kok-Leong; Crossley, Kay M; Crow, Justin; Morris, Meg E

    2017-08-01

    (1) To investigate whether a daily acute:chronic workload ratio informs injury risk in Australian football players; (2) to identify which combination of workload variable, acute and chronic time window best explains injury likelihood. Workload and injury data were collected from 53 athletes over 2 seasons in a professional Australian football club. Acute:chronic workload ratios were calculated daily for each athlete, and modelled against non-contact injury likelihood using a quadratic relationship. 6 workload variables, 8 acute time windows (2-9 days) and 7 chronic time windows (14-35 days) were considered (336 combinations). Each parameter combination was compared for injury likelihood fit (using R 2 ). The ratio of moderate speed running workload (18-24 km/h) in the previous 3 days (acute time window) compared with the previous 21 days (chronic time window) best explained the injury likelihood in matches (R 2 =0.79) and in the immediate 2 or 5 days following matches (R 2 =0.76-0.82). The 3:21 acute:chronic workload ratio discriminated between high-risk and low-risk athletes (relative risk=1.98-2.43). Using the previous 6 days to calculate the acute workload time window yielded similar results. The choice of acute time window significantly influenced model performance and appeared to reflect the competition and training schedule. Daily workload ratios can inform injury risk in Australian football. Clinicians and conditioning coaches should consider the sport-specific schedule of competition and training when choosing acute and chronic time windows. For Australian football, the ratio of moderate speed running in a 3-day or 6-day acute time window and a 21-day chronic time window best explained injury risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. Perceived vs. measured effects of advanced cockpit systems on pilot workload and error: are pilots' beliefs misaligned with reality?

    PubMed

    Casner, Stephen M

    2009-05-01

    Four types of advanced cockpit systems were tested in an in-flight experiment for their effect on pilot workload and error. Twelve experienced pilots flew conventional cockpit and advanced cockpit versions of the same make and model airplane. In both airplanes, the experimenter dictated selected combinations of cockpit systems for each pilot to use while soliciting subjective workload measures and recording any errors that pilots made. The results indicate that the use of a GPS navigation computer helped reduce workload and errors during some phases of flight but raised them in others. Autopilots helped reduce some aspects of workload in the advanced cockpit airplane but did not appear to reduce workload in the conventional cockpit. Electronic flight and navigation instruments appeared to have no effect on workload or error. Despite this modest showing for advanced cockpit systems, pilots stated an overwhelming preference for using them during all phases of flight.

  16. A Distinct Role of the Queen in Coordinated Workload and Soil Distribution in Eusocial Naked Mole-Rats

    PubMed Central

    Kutsukake, Nobuyuki; Inada, Masayuki; Sakamoto, Shinsuke H.; Okanoya, Kazuo

    2012-01-01

    We investigated how group members achieve collective decision-making, by considering individual intrinsic behavioural rules and behavioural mechanisms for maintaining social integration. Using a simulated burrow environment, we investigated the behavioural rules of coordinated workload for soil distribution in a eusocial mammal, the naked mole-rat (Heterocephalus glaber). We tested two predictions regarding a distinct role of the queen, a socially dominant individual in the caste system: the presence of a queen would increase the workload of other caste individuals, and the cues by a queen would affect the soil distribution. In experiment 1, we placed four individuals of various castes from the same colony into an experimental burrow. Workers exhibited the highest frequency of workload compared to other castes. The presence of a queen activated the workload by other individuals. Individuals showed a consistent workload in a particular direction so as to bias the soil distribution. These results suggest that individuals have a consensus on soil distribution and that the queen plays a distinct role. In experiment 2, we placed the odour of a queen in one of four cells and observed its effect on other individuals’ workload and soil distribution. Relative to other cells, individuals frequently dug in the queen cell so the amount of soil in the queen cell decreased. These results suggest that queen odour is an important cue in coordinated workload and soil distribution in this species. PMID:22957085

  17. Workload and the trajectory of marital satisfaction in newlyweds: job satisfaction, gender, and parental status as moderators.

    PubMed

    van Steenbergen, Elianne F; Kluwer, Esther S; Karney, Benjamin R

    2011-06-01

    Stress, on average, is bad for relationships. Yet stress at work is not always associated with negative relationship outcomes. The premise of the current study was that associations between workload and trajectories of marital satisfaction depend on circumstances that may constrain or facilitate partners' ability to negotiate their multiple roles. We hypothesized that the covariance between changes in workload and marital satisfaction over time should be moderated by (a) the extent to which spouses like their work, (b) their parental status, and (c) their gender. Analyses drawing upon eight waves of data on workload, work satisfaction, and marital satisfaction from 169 newlywed couples assessed over four years confirmed these predictions. Specifically, across couples, demands at work covaried positively with marital satisfaction for spouses who were more satisfied with their jobs. For nonparent couples, increases in husbands' workload covaried with increases in marital satisfaction for both spouses. For parent couples, however, increases in husbands' workload covaried with declines in marital satisfaction for both spouses. Unexpectedly, for parent couples, increases in wives' workload corresponded with increased marital satisfaction. Finally, consistent with predictions, wives were more affected by their husbands' workload than vice versa. Thus, tension between work and marriage is not inevitable, instead depending on circumstances that facilitate or impair performance in multiple roles. Couples, employers, and practitioners should recognize the role that external circumstances play in determining how work and marital life interact. 2011 APA, all rights reserved

  18. Cognitive consequences of clumsy automation on high workload, high consequence human performance

    NASA Technical Reports Server (NTRS)

    Cook, Richard I.; Woods, David D.; Mccolligan, Elizabeth; Howie, Michael B.

    1991-01-01

    The growth of computational power has fueled attempts to automate more of the human role in complex problem solving domains, especially those where system faults have high consequences and where periods of high workload may saturate the performance capacity of human operators. Examples of these domains include flightdecks, space stations, air traffic control, nuclear power operation, ground satellite control rooms, and surgical operating rooms. Automation efforts may have unanticipated effects on human performance, particularly if they increase the workload at peak workload times or change the practitioners' strategies for coping with workload. Smooth and effective changes in automation requires detailed understanding of the congnitive tasks confronting the user: it has been called user centered automation. The introduction of a new computerized technology in a group of hospital operating rooms used for heart surgery was observed. The study revealed how automation, especially 'clumsy automation', effects practitioner work patterns and suggest that clumsy automation constrains users in specific and significant ways. Users tailor both the new system and their tasks in order to accommodate the needs of process and production. The study of this tailoring may prove a powerful tool for exposing previously hidden patterns of user data processing, integration, and decision making which may, in turn, be useful in the design of more effective human-machine systems.

  19. Annotation and prediction of stress and workload from physiological and inertial signals.

    PubMed

    Ghosh, Arindam; Danieli, Morena; Riccardi, Giuseppe

    2015-08-01

    Continuous daily stress and high workload can have negative effects on individuals' physical and mental well-being. It has been shown that physiological signals may support the prediction of stress and workload. However, previous research is limited by the low diversity of signals concurring to such predictive tasks and controlled experimental design. In this paper we present 1) a pipeline for continuous and real-life acquisition of physiological and inertial signals 2) a mobile agent application for on-the-go event annotation and 3) an end-to-end signal processing and classification system for stress and workload from diverse signal streams. We study physiological signals such as Galvanic Skin Response (GSR), Skin Temperature (ST), Inter Beat Interval (IBI) and Blood Volume Pulse (BVP) collected using a non-invasive wearable device; and inertial signals collected from accelerometer and gyroscope sensors. We combine them with subjects' inputs (e.g. event tagging) acquired using the agent application, and their emotion regulation scores. In our experiments we explore signal combination and selection techniques for stress and workload prediction from subjects whose signals have been recorded continuously during their daily life. The end-to-end classification system is described for feature extraction, signal artifact removal, and classification. We show that a combination of physiological, inertial and user event signals provides accurate prediction of stress for real-life users and signals.

  20. The effects of display and autopilot functions on pilot workload for Single Pilot Instrument Flight Rule (SPIFR) operations

    NASA Technical Reports Server (NTRS)

    Hoh, Roger H.; Smith, James C.; Hinton, David A.

    1987-01-01

    An analytical and experimental research program was conducted to develop criteria for pilot interaction with advanced controls and displays in single pilot instrument flight rules (SPIFR) operations. The analytic phase reviewed fundamental considerations for pilot workload taking into account existing data, and using that data to develop a divided attention SPIFR pilot workload model. The pilot model was utilized to interpret the two experimental phases. The first experimental phase was a flight test program that evaluated pilot workload in the presence of current and near-term displays and autopilot functions. The second experiment was conducted on a King Air simulator, investigating the effects of co-pilot functions in the presence of very high SPIFR workload. The results indicate that the simplest displays tested were marginal for SPIFR operations. A moving map display aided the most in mental orientation, but had inherent deficiencies as a stand alone replacement for an HSI. Autopilot functions were highly effective for reducing pilot workload. The simulator tests showed that extremely high workload situations can be adequately handled when co-pilot functions are provided.