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  • 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.
351

Fatigue and Alarm Fatigue in Critical Care Nurses

Krinsky, Robin S. January 2015 (has links)
No description available.
352

Influence of Surface Finish on Bending Fatigue of Forged Steel Including Heating Method, Hardness, and Shot Cleaning Effects

McKelvey, Sean Ambrose 22 May 2011 (has links)
No description available.
353

Multiaxial Fatigue Testing Machine

Liu, Mu-Hsin January 2002 (has links)
No description available.
354

Structural reliability through robust design optimization and energy-based fatigue analysis

Letcher, Todd M. 27 August 2012 (has links)
No description available.
355

Upplevelser av fysisk aktivitet vid cancerrelaterad trötthet : en litteraturöversikt / Experiences of physical activity in cancer-related fatigue : a literature review

Oriya, Mayvand, Andersson, Moa January 2022 (has links)
Bakgrund Att drabbas av cancer, oavsett i vilken form, är påfrestande för individen på olika plan. Livet påverkas både fysiskt, psykiskt och socialt. Biverkningarna av sjukdomen och dess behandling kan variera mellan individer. En av de vanligaste biverkningarna är extrem trötthetskänsla, fatigue, och i och med detta kan många gånger den fysiska aktiviteten minska. Tidigare studier har visat att det finns flera positiva effekter av fysisk aktivitet både under och efter cancerbehandling. I denna litteraturöversikt sammanställs studier som har belyst hur patienter med cancerdiagnos har upplevt att deras fatigue har påverkats av fysisk aktivitet. Syfte Syftet med studien är att belysa upplevelser av fysisk aktivitet vid fatigue hos patienter med cancerdiagnos. Metod Denna icke-systematiska litteraturstudie grundar sig på 15 vetenskapliga artiklar, publicerade 2017–2022, som bestod av både kvantitativ och kvalitativ design. Sökningar genomfördes i databaserna PubMed och CINAHL samt genom manuell sökning. Integrerad analys användes för att sammanställa resultatet. Resultat Dataanalysen ledde fram till två huvudkategorier: Underlättar behandlingen och Ökad livskvalitet. Underlättar behandlingen indelades i underkategorierna Mindre biverkningar, Minskning av upplevda symtom och Ökad kunskap. Ökad livskvalitet indelades i underkategorierna Bättre sömn och mindre förekomst av depression, Ökad fysisk styrka och Mindre upplevd trötthet. Slutsats I denna studie framkommer att fysisk aktivitet har en positiv inverkan på fatigue hos patienter med cancer. Slutsatsen blir att vårdpersonal bör rekommendera fysisk aktivitet på en personcentrerad och individanpassad nivå till patienter under och efter cancerbehandling. Mer forskning behövs dock för att frambringa evidens om den fysiska aktivitets inverkan på cancerrelaterad fatigue. Detta kan leda till framtagande av riktlinjer för vårdpersonal om hur de kan öka patienternas kunskap, intresse och medvetenhet om de positiva effekterna fysisk aktivitet har vid cancer. / Background To be affected by cancer, regardless of its form, is very stressful for the individual in different ways. Life is impacted in a major way both physical and psychologically as well as socially. Side effects of the disease and its treatment vary largely between subjects. One of the most common side effects is fatigue, and due to this the individual´s physical activity can become diminished. Previous studies have shown that there are many positive effects of physical activity both during and after cancer treatment. In this literature review we compile studies that have illuminated how patients with a cancer diagnosis have experienced how their fatigue has been affected by physical activity. Aim The aim is to enlighten the experiences of physical activity in patients with fatigue related to cancer diagnoses. Method This non-systematic literature study bases its results on 15 scientific articles, published 2017–2022, amongst these are both quantitative as well as qualitative studies. Article searches were made in the PubMed and CINAHL databases as well as manual searches. Integrated data-analyses were used to analyse the articles. The chosen articles went through a quality assessment with the help of Sophiahemmet university’s assessment tool. Results The data analysis led to two main categories: Facilitates treatment and Increased quality of life. Facilitates treatment was divided into the subcategories Less side effects, Reduction of perceived symptoms and Increased knowledge. Increased quality of life was divided into the subcategories: Better sleep and reduced incidence of depression, Increased muscle strength and Decreased perceived fatigue. Conclusions In this study it became evident that physical activity has a positive effect on fatigue in patients with cancer. The conclusion shows that the healthcare staff should encourage and recommend physical activity in a personified as well as individually appropriated level to patients during and after their cancer treatment. However, more research is needed to produce evidence of the impact of physical activity on cancer-related fatigue. This can lead to the development of guidelines for healthcare professionals on how they can increase patients' knowledge, interest and awareness of physical activity and the positive effects for patients with cancer.
356

On couple stress in the mechanics of materials

Ellis, Robert William January 1966 (has links)
The couple stress theory as presented by Mindlin, Koiter, Stokes and others is reviewed with particular attention being given to stress concentration and size effects. That theory is compared on a qualitative and quantitative basis with Neuber's theory for stress concentration for very small or sharp notches and with observed notch sensitivity effects in aluminum and steel. It is established that, in order to explain observed elastic size effects in these materials, the new material constant ℓ which is characteristic of the couple stress theory must be on the order of magnitude of .02". In order to determine order of magnitude of the constant, a series of experiments was designed based on a thin plate analysis developed here. The plate theory uses the basic assumptions of classical plate theory as well as several, as explained in the text, necessary when couple stress is included. The formulation resulted in a set of equations for plate deflection including classical and couple stress terms in such a way that when the constant ℓ was allowed to be zero, the classical equations resulted. Experimentally, it was found that the couple stress effect in steel and aluminum is at least one order of magnitude too small to account for observed size effects as was suggested by Mindlin. In addition, the magnitude of ℓ was found to be such that its effect would undoubtedly be clouded by inhomogeneity and anisotropy of metals at the microstructural level. The results represent the only known experimental data at the time of publication dealing with couple stress in metals and would seem to be the next obvious step in the development of the theory which has proceeded on a purely mathematical plane. An alternate approach to account for the effects of microstructure in notch sensitivity is discussed. / Ph. D.
357

Software tools for computer-controlled fatigue testing

Bhatia, Sanjay 15 November 2013 (has links)
Past efforts at implementing Load Spectrum Generation and Neuber Control have centered around minicomputers and analog circuits. The use of a personal computer to implement the tasks is presented. On implementation of the load Spectrum Generation software, the response of the Materials Testing System was investigated for distortion and attenuation. In particular, the effect of the resolution of the waveform on the test system response was noted. There was negligible attenuation for full scale frequencies of up to 20 Hz. Greater waveform resolution was required at lower frequencies than at higher frequencies. On implementation of the Neuber Control program, the accuracy obtained at the Neuber hyperbolas was noted. Better accuracy was obtained at ramp frequencies below 0.1 Hz. Based on the results obtained after implementing the Load Spectrum Generator program and the Neuber Control program, the performance of the personal computer in controlling fatigue tests is evaluated. Cost effectiveness and versatility favor the use of a personal computer for the control of fatigue tests. / Master of Science
358

Modeling of active crack damage control and the active fatique damage control of adhesive joint

Li, Shi 22 August 2009 (has links)
Active damage control is a new technique which mimics the self-repairing capability of biological beings and can be used to greatly increase the structural integrity and fatigue life. This thesis describes two approaches used in active damage control: direct stress cancellation and indirect stress cancellation. Direct stress cancellation is illustrated using an example of active crack damage control with embedded shape memory alloy actuators. Both experimental and theoretical investigations have been conducted to analyze the damage control mechanism. The approach of indirect stress cancellation is demonstrated with active fatigue damage control of adhesive joints. The damage and active control mechanisms of the adhesive joints have been experimentally and theoretically investigated. / Master of Science
359

Investigations of flakeboard mat consolidation

Lenth, Christopher Allen 23 June 2009 (has links)
The response of a flake mat to the mechanical stress applied during consolidation is a function of mat structure, raw material properties and the environmental conditions created during pressing. This research project was aimed at improving the understanding of raw material behavior during the hot-pressing of wood based composites by examining the response of a wood flake mat to the compression encountered during press closure in the flakeboard manufacturing process. The structure of a flakeboard mat can be considered to be that of a cellular material, the properties of which are governed by the cellular geometry, or arrangement of cells, and the properties of the solid cell wall material. A method for quantifying the cellular structure of a wood flake mat was developed and implemented. The structure of thin mat sections and small flake mats was quantified using image analysis techniques. The applicability of theories developed for modelling the compressive behavior of cellular materials to the consolidation of wood flake mats was investigated using thin mat sections. Narrow mat sections and small laboratory mats has similar void sizes but significantly different void shapes. Void size was not significantly affected by flake orientation, but void shape was. / Master of Science
360

Development and Validation of a Brief Version of the Vanderbilt Fatigue Scale for Adults: The VFS-A-10

Hornsby, B.W.Y., Camarata, S., Cho, S.-J., Davis, H., McGarrigle, Ronan, Bess, F.H. 28 March 2023 (has links)
Yes / Objectives: Listening-related fatigue can be a significant problem for adults who struggle to hear and understand, particularly adults with hearing loss. However, valid, sensitive, and clinically useful measures for listening-related fatigue do not currently exist. The purpose of this study was to develop and validate a brief clinical tool for measuring listening-related fatigue in adults. Design: The clinical scale was derived from the 40-item version of the Vanderbilt Fatigue Scale for Adults (VFS-A-40), an existing, reliable, and valid research tool for measuring listening9 related fatigue. The study consisted of two phases. Phase 1 (N = 580) and Phase 2 (N = 607) participants consisted of convenience samples of adults recruited via online advertisements, clinical records review, and a pool of prior research participants. In Phase 1, results from item response theory (IRT) analyses of VFS-A-40 items were used to identify high quality items for the brief (10-item) clinical scale: the VFS-A-10. In Phase 2, the characteristics and quality of the VFS-A-10 were evaluated in a separate sample of respondents. Dimensionality was evaluated using exploratory factor analyses (EFA) and item quality and characteristics were evaluated using IRT. VFS-A-10 reliability and validity were assessed multiple ways. IRT reliability analysis was used to examine VFS-A-10 measurement fidelity. In addition, test-retest reliability was assessed in a subset of Phase 2 participants (n = 145) who completed the VFS-A-10 a second time approximately one month after their initial measure (range 5-90 days). IRT differential item functioning (DIF) was used to assess item bias across different age, gender, and hearing loss subgroups. Convergent construct validity was evaluated by comparing VFS-A-10 responses to two other generic fatigue scales and a measure of hearing disability. Known-groups validity was assessed by comparing VFS-A-10 scores between adults with and without self reported hearing loss Results: EFA suggested a unidimensional structure for the VFS-A-10. IRT analyses confirmed all test items were high quality. IRT reliability analysis revealed good measurement fidelity over a wide range of fatigue severities. Test-retest reliability was excellent (rs = .88, collapsed across participants). IRT DIF analyses confirmed the VFS-A-10 provided a valid measure of listening29 related fatigue regardless of respondent age, gender, or hearing status. An examination of associations between VFS-A-10 scores and generic fatigue/vigor measures revealed only weak31 to-moderate correlations (Spearman’s correlation coefficient rs = -.36 to .57). Stronger associations were seen between VFS-A-10 scores and a measure of perceived hearing difficulties (rs = .79 to .81) providing evidence of convergent construct validity. In addition, the VFS-A-10 was more sensitive to fatigue associated with self-reported hearing difficulties than generic measures. It was also more sensitive than generic measures to variations in fatigue as a function of degree of hearing impairment. Conclusions: These findings suggest that the VFS-A-10 is a reliable, valid, and sensitive tool for measuring listening-related fatigue in adults. Its brevity, high sensitivity, and good reliability make it appropriate for clinical use. The scale will be useful for identifying those most affected by listening-related fatigue and for assessing benefits of interventions designed to reduce its negative effects. / Starkey Inc, NIH National Institute on Deafness and Other Communication Disorders (NIDCD) Grant #R21DC012865, NICHD Grant P30HD15052 to the Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt Institute for Clinical and Translational Research grant (UL1 TR000445 from NCATS/NIH) / The full-text of this article will be released for public view at the end of the publisher embargo on 1 Sep 2024.

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