• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 316
  • 46
  • 42
  • 42
  • 24
  • 14
  • 9
  • 7
  • 7
  • 7
  • 7
  • 7
  • 7
  • 6
  • 5
  • Tagged with
  • 814
  • 814
  • 169
  • 138
  • 134
  • 119
  • 114
  • 103
  • 90
  • 89
  • 74
  • 70
  • 66
  • 59
  • 58
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Taxonomy of short-term within-person variability in job performance Review and Empirical Assessment

Stuti Thapa Magar (9183089) 05 August 2023 (has links)
<p>Recent theoretical works and methodological advancements in organizational psychology have highlighted the necessity of a within-person perspective on organizational constructs. Past research suggests that focusing on within-person variation as an outcome can inform us of organizational processes that would not be possible with a static or mean-level approach. As such, the study of performance, on both intra- and inter-individual levels, is incomplete without addressing the nature of intraindividual variations and predictors of their short-term changes (i.e., dynamics). To address this, I first compiled a list of dynamic features from affective, personality, and cognitive dynamics and used it to develop a taxonomy of short-term performance variations (e.g., variability, inertia, stability, diurnal variation) and then conducted a systematic review of empirical works on performance variability to understand its associated theoretical constructs and their predictors. In the second part of my dissertation, I empirically examined the different forms of short-term performance dynamics (mean, maximum, minimum, variability, stability, inertia, week trends, day trends) using two weeks-long experience sampling data from working adults and a) investigated the extent to which they are distinct constructs and whether they have test-retest reliability, and b) tested what situational, time-specific, individual variables are most predictive of each form. I collected ESM data from 237 full-time working participants four times a day for two weeks with a week break in the middle (total observations = 10,315, average response rate = 48.3). I found that there was a high test-retest reliability for specific dynamic features, particularly those of OCB. In addition, I found that there were unique predictors for the same performance domain depending on how their variations were operationalized. </p>
412

A generalizable method and case application for development and use of the Aviation Systems – Trust Survey (AS-TS).

Hicks, Jamison 12 May 2023 (has links) (PDF)
Automated systems are integral in the development of modern aircraft, especially for complex military aircraft. Pilot Trust in Automation (TIA) in these systems is vital for optimizing the pilot-vehicle interface and ensuring pilots use the systems appropriately to complete required tasks. The objective of this research was to develop and validate a TIA scale and survey methodology to identify and mitigate trust deficiencies with automated systems for use in Army Aviation testing. There is currently no standard TIA assessment methodology for U.S. Army aviation pilots that identifies trust deficiencies and potential mitigations. A comprehensive literature review was conducted to identify prominent TIA factors present in similar studies. The compiled list of factors and associated definitions were used in a validation study that utilized the Analytic Hierarchy Process (AHP) as a pair-wise comparison tool to identify TIA factors most relevant to Army pilots. A notional survey, the Aviation Systems – Trust Survey (AS-TS), was developed from the identified factors and pilots were used as subjects in scenario-based testing to establish construct validity for the survey. Exploratory factor analysis was conducted after data collection and a validated survey was produced. A follow-on study interviewed Army test and evaluation experts to refine the survey methodology and ensure appropriate context for the recommended mitigations. A final packet was developed that included instructions for the rating scale, associated item definitions, and recommended mitigations for trust deficiencies. Future research will focus on other Army demographics to determine the generalizability of the AS-TS.
413

Supporting Flight Control for UAV-Assisted Wilderness Search and Rescue Through Human Centered Interface Design

Cooper, Joseph L. 15 November 2007 (has links) (PDF)
Inexpensive, rapidly deployable, camera-equipped Unmanned Aerial Vehicle (UAV) systems can potentially assist with a huge number of tasks. However, in many cases such as wilderness search and rescue (WiSAR), the potential users of the system may not be trained as pilots. Simple interface concepts can be used to build an interaction layer that allows an individual with minimal operator training to use the system to facilitate a search or inspection task. We describe an analysis of WiSAR as currently accomplished and show how a UAV system might fit into the existing structure. We then discuss preliminary system design efforts for making UAV-enabled search possible and practical. Finally, we present both a carefully controlled experiment and partially structured field trials that illustrate principles for making UAV-assisted search a reality. Our experiments show that the traditional method for controlling a camera-enabled UAV is significantly more difficult than integrated methods. Success and troubles during field trials illustrate several desiderata and information needs for a UAV search system.
414

Human-Swarm Interaction: Effects on Operator Workload, Scale, and Swarm Topology

Pendleton, Brian O. 04 September 2013 (has links) (PDF)
Robots, including UAVs, have found increasing use in helping humans with dangerous and difficult tasks. The number of robots in use is increasing and is likely to continue increasing in the future. As the number of robots increases, human operators will need to coordinate and control the actions of large teams of robots. While multi-robot supervisory control has been widely studied, it requires that an operator divide his or her attention between robots. Consequently, the use of multi-robot supervisory control is limited by the number of robots that a human or team of humans can reasonably control. Swarm robotics -- large numbers of low-cost robots displaying collective behaviors -- offers an alternative approach by providing the operator with a small set of inputs and parameters that alter the behavior of a large number of autonomous or semi-autonomous robots. Researchers have asserted that this approach is more scalable and offers greater promise for managing huge numbers of robots. The emerging field of Human-Swarm Interaction (HSI) deals with the effective management of swarms by human operators. In this thesis we offer foundational work on the effect of HSI (a) on the individual robots, (b) on the group as a whole, and (c) on the workload of the human operator. We (1) show that existing general swarm algorithms are feasible on existing robots and can display collective behaviors as shown in simulations in the literature, (2) analyze the effect of interaction style and neighborhood type on the swarm's topology, (3) demonstrate that operator workload stays stable as the size of the swarm increases, but (4) find that operator workload is influenced by the interaction style. We also present considerations for swarm deployment on real robots.
415

Evaluation and Validation of Distraction Detection Algorithms on Multiple Data Sources

Mehrotra, Shashank 25 October 2018 (has links)
This study aims to evaluate algorithms designed to detect distracted driving. This includes the comparison of how efficiently they detect the state of distraction and likelihood of a crash. Four algorithms that utilize measures of cumulative glance, past glance behavior, and glance eccentricity were used to understand the distracted state of the driver and were validated on two separate data sources (i.e., simulator and naturalistic data). Additionally, an independent method for distraction detection was designed using data mining methods. This approach utilized measures like steering degree, lane offset, lateral and longitudinal velocity, and acceleration. The results showed a higher likelihood of distracted events when cumulative glances were considered. However, the state of distraction was observed to be higher when glance eccentricity was added. Additionally, it was observed that glance behavior using the four legacy algorithms were better detectors of the state of distraction as compared to the data mining method that used vehicular measures. This research has implications in understanding the state of distraction, predicting the power of different methods, and comparing approaches in different contexts (naturalistic vs simulator). These findings provide the fundamental building blocks towards designing advanced mitigation systems that give drivers feedback in instances of high crash likelihood.
416

Warning Compliance: Effects Of Stress And Working Memory

Helmick-Rich, Jessica 01 January 2005 (has links)
This study investigated the effects of cross-modality warning presentation and retention in a dual-task paradigm in a simulated military environment under various task-induced stress levels. It was also intended to determine what role working memory played in the mode of warning presentation that resulted in the highest retention and subsequent compliance. An all within participant design was created in order to determine if scores on working memory span tasks predicted performance across the varying forms of warning presentation. Furthermore, task-induced stress levels were varied over the course of the experiment to identify if workload transitions affected performance. Results revealed that when the presentation format and the response format matched (e.g., verbal-verbal), behavioral compliance was greater then when presentation and response format were mismatched (e.g., verbal-pictorial). Thus, it is not necessarily the presentation type that affects compliance, but the combination of presentation and response mode. Analysis also revealed that the pictorial-pictorial warning combination resulted in greater behavioral compliance compared to verbal-verbal or written-written combinations. The format of warning presentation did not affect performance on the operational tasks as predicted. Thus, the visual/spatial operational task, regardless of its complexity was not interrupted in timesharing with intra-modal warning presentations or cross-modal time-sharing. As predicted, task based stress affected the WCCOM task in all experimental procedures. Results further revealed that as task demand increased, performance on the WCCOM task decreased. Task demand did affect the operational tasks, the shooting and the navigation tasks. The shooting task, which was less complex than the navigation task was not affected by lower levels of task demand, but at the greatest level of demand (eight warnings) performance in the operational task, degraded. Degradations in performance on the more complex task, the navigation task, materialized at a moderate level of task demand (four warnings). For subjective ratings, task demand did affect workload ratings. As the task demand increased, the subjective workload ratings also increased, revealing a true association between workload and subjective ratings. The working memory separability hypothesis was supported by the working memory span tasks, but consequently they were not predictive of the warning presentation format.
417

Impact of Interruption Frequency on Nurses' Performance, Satisfaction, and Cognition During Patient-Controlled Analgesia Use in the Simulated Setting

Campoe, Kristi 01 January 2015 (has links)
Problem: Interruption during medication administration is a significant patient safety concern within health care, especially during the administration of high risk medications in nursing. Patient-controlled analgesia (PCA) devices are frequently associated with adverse events and have a four-fold increased risk of patient injury compared to non-PCA related adverse events. While the nature and frequency of interruptions have been established for nurses* medication processes, the impact of interruption frequency on nurses* PCA interaction has not been fully measured or described. Purpose: The purposes of this study were to quantify the impact of interruption frequency on registered nurses* (RN) performance, satisfaction, and cognitive workload during PCA interaction, and to determine nurses* perceptions of the impact of interruption frequency. Methods: This study employed a mixed-method design. First, an experimental repeated measures design was used to quantify the impact of interruption frequency on a purposive sample of nine medical-surgical RNs. The RNs completed PCA programming tasks in a simulated laboratory nursing environment for each of four conditions where interruption frequency was pre-determined. Four established human factors usability measures were completed for each of the four test conditions. The research questions were answered using repeated measures analysis of variance with (RM-ANOVA), McNamar*s test, and Friedman*s test. After each experiment, semi-structured interviews were used to collect data that were analyzed using inductive qualitative content analysis to determine RNs* perceptions of the impact of interruption frequency. Results: Results of the RM-ANOVA were significant for the main effect of interruption frequency on efficiency F(3,24)=9.592, p = .000. McNemar*s test did not show significance for the impact of interruption frequency on effectiveness (accuracy). Friedman test showed participant satisfaction was significantly impacted by interruption frequency (x2=9.47, df=3, p=0.024). Friedman test showed no significance for the main effect of interruption frequency on cognitive workload scores by condition type (x2=1.88, df=3, p=0.599). Results of the qualitative content analysis revealed two main categories to describe nurses* perception of interruption frequency: the nature of interruptions and nurses* reaction to the interrupted work environment. Discussion/Implications: The results suggested that interruption frequency significantly affected task completion time and satisfaction for participants but not participant accuracy or cognitive workload. A high error rate during PCA programming tasks indicated the need to evaluate the conditions in which RNs complete PCA programming as each error presents potential risk of patient harm. RNs* described the impact of interruption frequency as having a negative impact on the work environment and subsequently implement compensating strategies to counterbalance interruptions. RNs* perceived that patient safety was negatively impacted by frequent interruption. RNs experienced negative intrapersonal consequences as a results of frequent interruption. Additional study is needed to better understand the impact of interruption frequency on RNs* performance accuracy and cognitive workload.
418

Assessment Of Instructional Presentation For Emergency Evacuation Assistive Technology

Boyce, Michael 01 January 2014 (has links)
It is often the case that emergency first responders are well equipped and trained to deal with a situation that involves evacuation of someone with a physical disability. However, emergency responders are not always the first line of defense, or they may be otherwise occupied with assisting others. This research examined the effects of instructions for emergency stair travel devices on untrained or novice users. It was hypothesized that through redesign of the evacuation instructions, untrained individuals would be able to successfully prepare an evacuation chair and secure someone with a disability more effectively and efficiently. A prepost study design was used with an instructional redesign occurring as the manipulation between phases. There was an improved subjective understanding and improved performance metrics, such as reduced time on task and a reduction of the number of instructional glances, across three evacuation chairs when using the redesigned instruction sets. The study demonstrated that visual instruction style can account for a significant portion of explained variance in the operation of emergency stair travel devices. It also showed that improvements in instruction style can reduce time on task across device type and age group. The study failed to demonstrate that there was a performance decrement for older adults in comparison to younger adults because of the cognitive slowing of older adult information processing abilities. Results from this study can be used to support future iterations of the Emergency Stair Travel Device Standard (RESNA ED-1) to ensure that instructional design is standardized and optimized for the best performance possible.
419

Does Safety Culture Predict Clinical Outcomes?

Wilson, Katherine Ann 01 January 2007 (has links)
Patient safety in healthcare has become a national objective. Healthcare organizations are striving to improve patient safety and have turned to high reliability organizations as those in which to model. One initiative taken on by healthcare is improving patient safety culture--shifting from one of a 'no harm, no foul' to a culture of learning that encourages the reporting of errors, even those in which patient harm does not occur. Lacking from the literature, however, is an understanding of how safety culture impacts outcomes. While there has been some research done in this area, and safety culture is argued to have an impact, the findings are not very diagnostic. In other words, safety culture has been studied such that an overall safety culture rating is provided and it is shown that a positive safety culture improves outcomes. However, this method does little to tell an organization what aspects of safety culture impact outcomes. Therefore, this dissertation sought to answer that question but analyzing safety culture from multiple dimensions. The results found as a part of this effort support previous work in other domains suggesting that hospital management and supervisor support does lead to improved perceptions of safety. The link between this support and outcomes, such as incidents and incident reporting, is more difficult to determine. The data suggests that employees are willing to report errors when they occur, but the low occurrence of such reportable events in healthcare precludes them from doing so. When a closer look was taken at the type of incidents that were reported, a positive relationship was found between support for patient safety and medication incidents. These results initially seem counterintuitive. To suggest a positive relationship between safety culture and medication incidents on the surface detracts from the research in other domains suggesting the opposite. It could be the case that an increase in incidents leads an organization to implement additional patient safety efforts, and therefore employees perceive a more positive safety culture. Clearly more research is needed in this area. Suggestions for future research and practical implications of this study are provided.
420

Perception And Displays For Teleoperated Robots

Upham Ellis, Linda 01 January 2008 (has links)
In remote or teleoperational tasks involving humans and robots, various aspects of the remote display system may greatly influence the individual's interactions with the teleoperated entity. This dissertation examined various configurations of display systems on several measures of operator performance, physiological states, and perceptions of the task. Display configurations included altering the camera placement (attached to the robot or placed overhead), screen orientation (horizontal or vertical), and screen size (small or large). Performance was measured in terms of specific task goals, accuracies, strategies, and completion times. Physiological state was assessed through physiological markers of arousal, specifically heart rate and skin conductance. Operator perception of the task was measured with a self-reported perception of workload and frustration. Scale model live simulation was used to create a task driven environment to test the display configurations. Screen size influenced performance on complex tasks in mixed ways. Participants using a small screen exhibited better problem solving strategies in a complex driving task. However, participants using the large screen exhibited better driving precision when the task required continual attention. These findings have value in design decisions for teleoperated interfaces where the advantages and disadvantages of screen size must be considered carefully. Orientation of the visual information seems to have much less impact on the operator than the source of the information, though it was an important factor of the display system when taken together with screen size and camera view. Results show strong influence of camera placement on many of the performance variables. Interestingly, the participants rated a higher frustration in the overhead condition, but not a higher task load, indicating that while they realized that the task was frustrating and perhaps they could have done better, they did not recognize the task as overloading. This was the case even though they took longer to complete the task and experienced more errors related to turning in the overhead camera condition. This finding may indicate a potential danger for systems in which the operator is expected to recognize when he or she is being overloaded. This type of performance decrease due to added frames of reference may be too subtle to register in the operator's self awareness

Page generated in 0.116 seconds