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FACTORS RELATED TO STRESS IN NURSING STUDENTS
Title
FACTORS RELATED TO STRESS IN NURSING STUDENTS.
Creator
Shultz, Marie, Covelli, Maureen, University of Central Florida
Abstract / Description
The purpose of this review of literature was to explore and critically analyze relevant literature regarding stress factors and the consequences of stress in nursing students. Findings from this review of literature aimed to provide a better understanding of stress factors and the physical and psychological impact of stress on nursing students. Information was collected from the Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and MEDLINE- EBSCOhost databases to explore...
Show moreThe purpose of this review of literature was to explore and critically analyze relevant literature regarding stress factors and the consequences of stress in nursing students. Findings from this review of literature aimed to provide a better understanding of stress factors and the physical and psychological impact of stress on nursing students. Information was collected from the Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and MEDLINE- EBSCOhost databases to explore what research has been conducted and to assess the current knowledge base. Analysis of the literature indicated that nursing students reported experiencing increased levels of stress during the academic year. Nursing students reported higher levels of stress in conjunction with elevated external stressors, including increased responsibilities and course requirements. Analysis of the findings suggested that factors related to stress in nursing students arose from clinical sources, academic sources, and personal sources. Further analysis indicated that experiencing elevated levels of stress had a negative impact on the student. Increased levels of stress, combined with poor coping mechanisms, may lead to poor academic performance and burn-out among nursing students. Future research may evaluate means to reduce stress levels and mitigate stress in nursing students through targeting specific causative factors. Findings from this review of literature aim to influence student management of stress.
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Date Issued
2011
Identifier
CFH0003825, ucf:44778
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0003825
STRESS INTENSITY FACTOR DEPENDENCE OF HG-AL LIQUID METAL EMBRITTLEMENT
Title
STRESS INTENSITY FACTOR DEPENDENCE OF HG-AL LIQUID METAL EMBRITTLEMENT.
Creator
Keller, Scott, Gordon, Ali, University of Central Florida
Abstract / Description
When high strength aluminum alloys are subjected to liquid metals, physical and chemical reactions ensue resulting in what is known as liquid metal embrittlement (LME). A subset of environmentally-assisted cracking, LME is exhibited when a liquid metal, e.g. Hg or Ga, comes into intimate contact with a solid metal having significant susceptibility. As mechanical loads are applied, the interaction between the two metals results in a reduction in the flow properties of the solid metal. Several...
Show moreWhen high strength aluminum alloys are subjected to liquid metals, physical and chemical reactions ensue resulting in what is known as liquid metal embrittlement (LME). A subset of environmentally-assisted cracking, LME is exhibited when a liquid metal, e.g. Hg or Ga, comes into intimate contact with a solid metal having significant susceptibility. As mechanical loads are applied, the interaction between the two metals results in a reduction in the flow properties of the solid metal. Several theories have been proposed to identify the underlying microstructural failure mechanism; however, none have been widely accepted, as failures can typically incorporate features common to several failure theories. In an effort to confirm, extend or replace the physically-based theories, fracture mechanics experiments on Al 7075–T651 in liquid mercury have been conducted. Experiments were conducted in a custom environmental chamber capable of exposing specimens to liquid environments while applying a mechanical load. Through both plane-strain fracture and stress intensity factor-dependent (SIF) tests, fracture toughness values along with incubation periods were analyzed and provided data for a load-based theory of LME. These mechanical test data, along with metallographic analysis, show that the phenomena of LME is both strongly time- and SIF-dependent.
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Date Issued
2009
Identifier
CFE0002893, ucf:48033
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0002893
FRIEND/FOE IDENTIFICATION ACCURACY AND SHOOTING PERFORMANCE: EFFECTS OF PRIOR TASK LOADING AND TIME PRESSURE
Title
FRIEND/FOE IDENTIFICATION ACCURACY AND SHOOTING PERFORMANCE: EFFECTS OF PRIOR TASK LOADING AND TIME PRESSURE.
Creator
Burke, Kelly, Hancock, Peter, University of Central Florida
Abstract / Description
The current dismounted soldier and the soldier of the future will be  loaded' with more information processing tasks while they perform shooting tasks. It is conceivable that some increased level of cognitive tasking may be performed simultaneously with required shooting tasks. The effect of cognitive load on shooting performance has been previously examined (Scribner and Harper, 2001). This study concentrated on the effect of various cognitive workload demands on a friend-foe...
Show moreThe current dismounted soldier and the soldier of the future will be  loaded' with more information processing tasks while they perform shooting tasks. It is conceivable that some increased level of cognitive tasking may be performed simultaneously with required shooting tasks. The effect of cognitive load on shooting performance has been previously examined (Scribner and Harper, 2001). This study concentrated on the effect of various cognitive workload demands on a friend-foe discrimination shooting task in a single- and dual-task scenario. In light of this, it is imperative that the soldier not be overburdened mentally, which may result in decreased survivability and lethality. Specifically, this study was designed to examine the ability of the soldier to perform friend-foe target discrimination and shooting accuracy, with varying target exposure times, friendly target signatures, and varying cognitive load demands (working memory recall task). Using the Small Arms Simulator Testbed (SAST) we examined the effects of manipulations of working memory load and sustained information transfer, on shooting performance (as measured by target acquisition and friend/foe discrimination indices). Additionally, we investigated subjective measures of workload and stress. A secondary task, administered aurally, was given to subjects to attend to while they performed shooting (friend/foe discrimination task) scenarios: working memory recall task. Each type of task consisted of three levels of difficulty. Analysis of variance revealed significant differences for the memory recall task during shooting and non-shooting conditions. Furthermore, results showed that workload increased as a function of task demand, with associated decreases in shooting performance.
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Date Issued
2007
Identifier
CFE0001681, ucf:47212
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0001681
WARNING COMPLIANCE: EFFECTS OF STRESS AND WORKING MEMORY
Title
WARNING COMPLIANCE: EFFECTS OF STRESS AND WORKING MEMORY.
Creator
Helmick-Rich, Jessica, Hancock, Peter A, University of Central Florida
Abstract / Description
ABSTRACT 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...
Show moreABSTRACT 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.
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Date Issued
2005
Identifier
CFE0000725, ucf:46624
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0000725
The Impact of Automation and Stress on Human Performance in UAV Operation
Title
The Impact of Automation and Stress on Human Performance in UAV Operation.
Creator
Lin, Jinchao, Matthews, Gerald, Reinerman, Lauren, Szalma, James, Funke, Gregory, University of Central Florida
Abstract / Description
The United States Air Force (USAF) has increasing needs for unmanned aerial vehicle (UAV) operators. Automation may enable a single operator to manage multiple UAVs at the same time. Multi-UAV operation may require a unique set of skills and the need for new operators calls for targeting new populations for recruitment. The objective of this research is to develop a simulation environment for studying the role of individual differences in UAV operation under different task configurations and...
Show moreThe United States Air Force (USAF) has increasing needs for unmanned aerial vehicle (UAV) operators. Automation may enable a single operator to manage multiple UAVs at the same time. Multi-UAV operation may require a unique set of skills and the need for new operators calls for targeting new populations for recruitment. The objective of this research is to develop a simulation environment for studying the role of individual differences in UAV operation under different task configurations and investigate predictors of performance and stress. Primarily, the study examined the impact of levels of automation (LOAs), as well as task demands, on task performance, stress and operator reliance on automation. Two intermediate LOAs were employed for two surveillance tasks included in the simulation of UAV operation. Task demand was manipulated via the high and low frequency of events associated with additional tasks included in the simulation. The task demand and LOA manipulations influenced task performance generally as expected. The task demand manipulations elicited higher subjective distress and workload. LOAs did not affect operator workload but affected reliance behavior. Also, this study examined the role of individual differences in simulated UAV operation. A variety of individual difference factors were associated with task performance and with subjective stress response. Video gaming experience was linked to lower distress and better performance, suggesting possible transfer of skills. Some gender differences were revealed in stress response, task performance, but all the gender effects became insignificant with gaming experience controlled. Generally, the effects of personality were consistent with previous studies, except some novel findings with the performance metrics. Additionally, task demand was found to moderate the influence of personality factors on stress response and performance metrics. Specifically, conscientiousness was associated with higher subjective engagement and performance when demands were higher. This study supports future research which aims to improve the dynamic interfaces in UAV operation, optimize operator reliance on automation, and identify individuals with the highest aptitude for multi-UAV control.
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Date Issued
2017
Identifier
CFE0006951, ucf:51630
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006951
The Characterization of the Effects of Stress Concentrations on the Mechanical Behavior of a Micronic Woven Wire Mesh
Title
The Characterization of the Effects of Stress Concentrations on the Mechanical Behavior of a Micronic Woven Wire Mesh.
Creator
Kraft, Steven, Gordon, Ali, Bai, Yuanli, Gou, Jihua, University of Central Florida
Abstract / Description
Woven structures are steadily emerging as excellent reinforcing components in dual-phase composite materials subjected to multiaxial loads, thermal shock, and aggressive reactants in the environment. Metallic woven wire mesh materials display good ductility and relatively high specific strength and specific resilience. While use of this class of materials is rapidly expanding, significant gaps in mechanical behavior classification remain. This thesis works to address the mechanics of material...
Show moreWoven structures are steadily emerging as excellent reinforcing components in dual-phase composite materials subjected to multiaxial loads, thermal shock, and aggressive reactants in the environment. Metallic woven wire mesh materials display good ductility and relatively high specific strength and specific resilience. While use of this class of materials is rapidly expanding, significant gaps in mechanical behavior classification remain. This thesis works to address the mechanics of material knowledge gap that exists for characterizing the behavior of a metallic woven structure, composed of stainless steel wires on the order of 25 microns in diameter, and subjected to various loading conditions and stress risers. Uniaxial and biaxial tensile experiments, employing Digital Image Correlation (DIC) as a strain measurement tool, are conducted on woven wire mesh specimens incised in various material orientations, and with various notch geometries. Experimental results, supported by an ample analytic modeling effort, indicate that an orthotropic elastic constitutive model is reasonably capable of governing the macro-scale elasticity of the subject material. Also, the Stress Concentration Factor (SCF) associated with various notch geometries is documented experimentally and analytically, and it is shown that the degree of stress concentration is dependent on both notch and material orientation. The Finite Element Method (FEM) is employed on the macro-scale to expand the experimental test matrix, and to judge the effects of a homogenization assumption when modeling metallic woven structures. Additionally, plasticity of the stainless steel woven wire mesh is considered through experimental determination of the yield surface, and a thorough analytic modeling effort resulting in a modified form of the Hill yield criterion. Finally, meso-scale plasticity of the woven structure is considered, and the form of a multi-scale failure criterion is proposed and exercised numerically.
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Date Issued
2013
Identifier
CFE0004707, ucf:49825
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004707
Treatment Matching in PTSD: A Confirmatory Factor Analysis Based On Therapeutic Mechanisms of Action
Title
Treatment Matching in PTSD: A Confirmatory Factor Analysis Based On Therapeutic Mechanisms of Action.
Creator
Trachik, Benjamin, Bowers, Clint, Beidel, Deborah, Jentsch, Florian, University of Central Florida
Abstract / Description
The current study takes an initial step toward deriving a method for empirically based, theory-driven treatment matching in a military population suffering from PTSD. Along with the more overt symptoms of PTSD (e.g., persistent hyperarousal), secondary cognitive symptoms have also been shown to be significantly associated with avoidance and intrusive symptoms, as well as contribute to functional impairment. Based on the factor analytic and treatment literature for PTSD, it appears that there...
Show moreThe current study takes an initial step toward deriving a method for empirically based, theory-driven treatment matching in a military population suffering from PTSD. Along with the more overt symptoms of PTSD (e.g., persistent hyperarousal), secondary cognitive symptoms have also been shown to be significantly associated with avoidance and intrusive symptoms, as well as contribute to functional impairment. Based on the factor analytic and treatment literature for PTSD, it appears that there are two central mechanisms associated with beneficial therapeutic change that underlies both CPT and PE treatments (i.e., habituation, changes in cognitions). Additionally, different traumatic events and peritraumatic responses may be associated with unique symptom profiles and may necessitate targeted treatment. The present study proposes a novel approach to treatment matching based on the factor structure of PTSD and underlying mechanisms of treatment response. More broadly, this paper provides evidence for a broader understanding of peritraumatic responses and the potential implications of these responses for symptom profiles and illness trajectories.
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Date Issued
2014
Identifier
CFE0005727, ucf:50126
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005727