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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.
301

A Research on the Relationship between People¡¦s Perception of Community Health Building policy and Healthy Behavior ¡XA Case Study of Kaohusiung Indigenous Botanical Garden Community

Lin, Chih-Chung 20 July 2007 (has links)
none
302

The difference of environmental attitude and behavior between recyclers and non-recyclers

Huang, Suh-Ji 31 July 2002 (has links)
The difference of envirnomental attitude and behavior between the recyclers and non-recyclers.
303

Metamemory in multiple sclerosis

Claffey, Austin M. January 2010 (has links)
The concept of metamemory proposes that supplementary to typically measured memory abilities, memory monitoring and control processes are used to optimise learning. Accurate memory monitoring appears to be underpinned by a range of cognitive, and possibly affective, contributions. In populations with these deficits, metamemory has been shown to be impaired. In Multiple Sclerosis (MS), only a limited metamemory literature exists, surprising given that MS is a leading cause of disability among people of working age, and cognitive and mood disorder is common. Using structural equation modelling, this study of 100 people with MS explored factors contributing to performance on episodic Judgment of Learning, Retrospective Confidence and Feeling of Knowing. Given its negative influence on cognitive domains in MS, the impact of information processing deficits on metamemory was also investigated. Finally, memory self-report, a frequently used clinical indicator of memory functioning, was assessed. Findings suggest that memory complaint is associated with mood, and is unrelated to tested memory. Second, Retrospective Confidence Judgments were predictive of memory performance, even in the presence of memory impairment. Third, an unusual finding of maintained underconfidence at delay was observed in the Judgment of Learning task. Finally, Feeling of Knowing judgments related to executive, but not to memory ability. A novel finding in respect of this judgment was of processing speed relating negatively to accuracy, in the context of executive dysfunction. This suggests that some top-down direction of processing resources may be a factor in supporting accuracy, rather than the speed at which information is processed. Of all the task-based judgments, accuracy in this judgment was the only one with a reliable association with mood. Faster processing speed, executive dysfunction and least depression symptomatology related to low accuracy, perhaps typifying a profile of disinhibition seen in MS, characterised by poorly constrained processing and apparently elevated mood.
304

Surface Microstructure Evolution of Metallic Specimens Using the Large Chamber Scanning Electron Microscope

Egbujor, Grace 01 May 2015 (has links)
An initial study into the use of the large chamber scanning electron microscope (LCSEM) to interrogate the surface microstructure evolution of metallic specimens has been carried out. The LC-SEM located at Western Kentucky University is the largest instrument of its type at any university in the world. As such, unique measurements can be performed due to the size of its chamber and extended view of its optic system. Strain was varied for each individual specimen, and imaged using Secondary Electrons within the gauge length as well as near the grip position. Results will show progression of surface microstructures and nickel content of metallic specimens. Additionally, results will demonstrate the capability of the LC-SEM to carry out these types of measurements. Future measurements will include the incorporation of an in-situ uniaxial load frame for dynamic studies.
305

Development of advanced ferritic steels for high efficiency power generation plant

Qin, Guixiang January 2009 (has links)
E911 creep samples exposed to temperatures of 600˚C, 625˚C and 650˚C at differing stress levels were supplied by CORUS. The hardness of the gauge length that experienced both creep strain and temperature was found to be lower than that of the head where thermal softening only can be assumed. The changes in the morphology and size of precipitates were observed qualitatively by optical microscopy and Scanning Electron Microscopy. A creep fracture mechanism map of E911 steel was constructed with two modes of creep (transgranular and intergranular ). A fitted ellipse shape was used to characterise the irregular block shape by Electron Backscattered Diffraction (EBSD). It showed that the width of the block inside a prior austenite grain increases more rapidly in the gauge length than in the head; subgrain growth was also observed by EBSD. Transmission Electron Microscopy studies indicate that at 600°C E911 steel can reach up to 75647 hours creep rupture life (108MPa), which is due to the relatively small size of M23C6, Laves and M2X phases. However, Z phase precipitation results in a drop in creep resistance owing to the dissolution of fine MX phase and the transformation of M2X phase. At 625°C and 650°C, the creep rupture life decreases owing to the coarsening of Laves, M23C6 and M2X phases. Four experimental steel casts were prepared with varying levels of Ni and Cr to investigate the effect of these elements on Z phase formation. After 10,000 hours exposure, there was little evidence of Z phase in the samples studied and therefore it is difficult to draw definitive conclusions about the role of Ni or Cr in promoting Z phase formation. It is possible that the casts studied here will allow better conclusions to be drawn after exposing the samples to longer durations.
306

Mineraliseringar utmed REE-linjen i sydvästra Bergslagen

Linnros, Henrik January 2014 (has links)
This paper briefly summarizes Bergslagen as a bedrock province in order to give background to the genesis and presence of REE-bearing minerals (short for Rare Earth Elements) in the region. These mineralizations mainly occur along the REE-line, a line aproximately a hundred kilometers in length between Norberg in the north and Nora in the south with a width of a few kilometers. Situated in the southwest of Bergslagen it is currently one of only a few places in Sweden where REE-bearing iron oxide mineralizations are potentially economically viable for mining. Ore microscopy has been conducted in order to characterize an ore sample from Myrbacksfältet, one of few sulphide rich iron oxide mineralizations within the REE-line. Additionally, an electron microscope analysis of a sample from Stålklockan, a suspected REE-bearing mineralization also within the REE-line was confirmed by EDS (short for Energy Dispersive Spectrum) analysis. An interactive map has been made of the REE- line to aid with visualization in an attempt to collect all known geospatial-, mineral-  and bedrock information in one place. The map is available in PDF format in conjunction with this text. A static version of this map is presented under 4.1 (REE-linjen). / Berggrundsprovinsen Bergslagens regionala geologi beskrivs inledningsvis för att ge bakgrund till de fyndigheter av REE-förande mineral (eng. Rare Earth Elements; Sällsynta jordartsmetaller) som förekommer utmed en ungefär hundra kilometer lång och ett par kilometer bred zon. Detta geografiskt och mineralogiskt avgränsade område kallas REE-linjen och ligger i sydvästra Bergslagen. I detta område mellan Norberg i norr och Nora i söder finns idag några av de få potentiellt ekonomiskt brytbara fyndigheterna av REE-förande mineral i Sverige vilket har gjort en kartkonstruktion vari spatiell-, mineralogisk-, och berggrundsdata över området finns sammanställd meningsfull. En sådan karta har gjorts i ArcGIS och presenteras i interaktivt PDF format i anslutning till texten. Malmmikroskopisk karaktärisering av en sulfidrik järnmalm från Myrbacksfältet i REE-linjen, såväl som en elektronmikroskopisk EDS (Energy Dispersive Spectrum) analys av ett prov från Stålklockan i Riddarhyttans malmfält har genomförts.
307

A comparison of imaging methods using GPR for landmine detection and a preliminary investigation into the SEM for identification of buried objects

Gilmore, Colin G. 13 January 2005 (has links)
Part I: Various image reconstruction algorithms used for subsurface targets are reviewed. It is shown how some approximate wavefield inversion techniques: Stripmap Synthetic Aperture Radar (SAR), Kirchhoff Migration (KM) and Frequency-Wavenumber (FK) migration are developed from various models for wavefield scattering. The similarities of these techniques are delineated both from a theoretical and practical perspective and it is shown that Stripmap SAR is, computationally, almost identical to FK migration. A plane wave interpretation of both Stripmap SAR and FK migration is used to show why they are so similar. The electromagnetic assumptions made in the image reconstruction algorithms are highlighted. In addition, it is shown that, theoretically, FK and KM are identical. Image reconstruction results for KM, Stripmap SAR and FK are shown for both synthetic and experimental Ground Penetrating Radar (GPR) data. Subjectively the reconstructed images show little difference, but computationally, Stripmap SAR (and therefore, FK migration) are much more efficient. Part II: A preliminary investigation into the use of the Singularity Expansion Method (SEM) for use in identifying landmines is completed using a Finite-Difference Time-Domain code to simulate a simplified GPR system. The Total Least Squares Matrix Pencil Method (TLS-MPM) is used to determine the complex poles from an arbitrary late-time signal. Both dielectric and metallic targets buried in lossless and lossy half-spaces are considered. Complex poles (resonances) of targets change significantly when the objects are buried in an external medium, and perturbation formulae for Perfect Electric Conductor (PEC) and dielectric targets are highlighted and used. These perturbation formulae are developed for homogenous surrounding media, and their utilization for the half-space (layered medium) GPR problem causes inaccuracies in their predictions. The results show that the decay rate (real part) of the complex poles is not suitable for identification in this problem, but that with further research, the resonant frequency (imaginary part) of the complex poles shows promise as an identification feature.
308

A comparison of imaging methods using GPR for landmine detection and a preliminary investigation into the SEM for identification of buried objects

Gilmore, Colin G. 13 January 2005 (has links)
Part I: Various image reconstruction algorithms used for subsurface targets are reviewed. It is shown how some approximate wavefield inversion techniques: Stripmap Synthetic Aperture Radar (SAR), Kirchhoff Migration (KM) and Frequency-Wavenumber (FK) migration are developed from various models for wavefield scattering. The similarities of these techniques are delineated both from a theoretical and practical perspective and it is shown that Stripmap SAR is, computationally, almost identical to FK migration. A plane wave interpretation of both Stripmap SAR and FK migration is used to show why they are so similar. The electromagnetic assumptions made in the image reconstruction algorithms are highlighted. In addition, it is shown that, theoretically, FK and KM are identical. Image reconstruction results for KM, Stripmap SAR and FK are shown for both synthetic and experimental Ground Penetrating Radar (GPR) data. Subjectively the reconstructed images show little difference, but computationally, Stripmap SAR (and therefore, FK migration) are much more efficient. Part II: A preliminary investigation into the use of the Singularity Expansion Method (SEM) for use in identifying landmines is completed using a Finite-Difference Time-Domain code to simulate a simplified GPR system. The Total Least Squares Matrix Pencil Method (TLS-MPM) is used to determine the complex poles from an arbitrary late-time signal. Both dielectric and metallic targets buried in lossless and lossy half-spaces are considered. Complex poles (resonances) of targets change significantly when the objects are buried in an external medium, and perturbation formulae for Perfect Electric Conductor (PEC) and dielectric targets are highlighted and used. These perturbation formulae are developed for homogenous surrounding media, and their utilization for the half-space (layered medium) GPR problem causes inaccuracies in their predictions. The results show that the decay rate (real part) of the complex poles is not suitable for identification in this problem, but that with further research, the resonant frequency (imaginary part) of the complex poles shows promise as an identification feature.
309

Performance management, organisational commitment, and Employee outcomes: A case in Thai policing

Songaek Patcharawit Unknown Date (has links)
Performance management is a holistic approach to organisational improvement that integrates individual and organisational goals and fosters cooperation between supervisors and employees to develop a shared understanding of work expectations. The literature further clarifies a performance management system as having four practices – goal setting, performance appraisal, employee development, and rewards. The conceptualisation of performance management draws on the dominant HRM framework of bundles of “high commitment” work practices whereby an organisation involves employees in its goals and activities to promote their discretionary motivation towards desired outcomes and overall improvement. However, there has been limited research on fully theorising performance management with the four key components. Although some empirical studies have tested the performance management concept, they focus narrowly on only a few of these components. Moreover, empirical research has omitted the role of organisational commitment in explaining the commitment based mechanisms in which the performance management bundle operates to inspire employees to improve their contributions in a workplace. To address these gaps, this study proposes a conceptual model to empirically investigate the linkages between performance management and three employee outcomes of task performance, organisational citizenship behaviour (OCB), and turnover intention as mediated by two focal bases of organisational commitment – affective and continuance dimensions. These relationships are explored in the Thai Police Service. The mediating effects are based on the argument that satisfactory work conditions inherent in performance management may carry perceptions of both organisational care and support and also accumulated investments underlying the development of the affective and continuance dimensions, respectively. While both mediators are hypothesised to decrease turnover, affective commitment tends to increase task performance and OCB, and continuance commitment tends to be either unrelated or negatively related to both performance variables. Furthermore, because organisational characteristics in police forces are generally distinct from others, police culture was included in the conceptual model to examine the incremental contribution of performance management to changes in the employee outcomes. This research embraced three related studies. Four focus groups of 27 patrol officers were conducted in Study 1 to explore key dimensions of police culture and examine officers’ understanding of performance management practices. Having developed a written questionnaire to test the conceptual model, Study 2 surveyed 161 patrol officers returning 152 usable questionnaires in order to assess the meaning equivalence and applicability of the translated measures of all constructs (from English to Thai) in the model, and to determine their validity and reliability. In the third and main study, a revised questionnaire was used to survey 516 patrol officers, 454 of which returned usable questionnaires that were half split randomly (224 and 230) to enable the analysis in two parts. Based on structural equation modeling (SEM), the first part allowed the measurement properties to be re-explored due to questionnaire revisions, and then confirmed, using both respective samples. The second part was based on the Partial Least Squares (PLS) technique for testing the conceptual model using the second sample. Overall, the empirical analysis shows that performance management not only accounted for affective commitment but also, to a lesser extent, continuance commitment. Performance management also was related both directly with task performance and indirectly through affective commitment, only directly with OCB, and only indirectly (fully mediated) with turnover intention through continuance commitment. Even after controlling for the impact of police culture and demographic characteristics, the predictive strength of performance management remained significant. The hypothesized relationships of affective commitment to OCB and turnover, however, were not supported. The follow up analysis revealed that the positive relationship between the former actually existed, but was conditional upon a high level of continuance commitment. Some of the major theoretical implications include the conceptualisation of performance management as confirmed with four components, a better understanding of the role of organisational commitment in explicating the high commitment mechanisms of performance management and the impact of organisational culture on the operation of performance management. From a practical perspective, organisations are encouraged to establish the holistic process of performance management to elevate employee performance and overall productivity and to emphasise voluntary and supportive aspects of the implementation of performance management to ensure its positive effects through affective rather than continuance commitment. For police organisations particularly, management should strive for interventions that reinforce values of progressive thinking, people-centred operations, and cooperation to supplement the performance management system. Finally, the conclusion discusses limitations and directions for future research.
310

Effect of PCI blending on combustion characteristics for iron-making

Gill, Trilochan Singh, Materials Science & Engineering, Faculty of Science, UNSW January 2009 (has links)
The PCI technology is well established for reducing the consumption of economic and environmentally expensive coke in blast furnace iron-making. Often, coal blends show unexpected combustion performance which cannot be explained on the basis of individual coal properties particularly coal rank and volatile matter. Several coals were combusted in this study under controlled conditions in a drop tube furnace. Fixed bed reactor, XRD, SEM and BET analyses were used to understand the mechanism of combustion of coal blends. Burnout of the coal blends did not change linearly with volatile matter of blends. The study demonstrated that combustion behaviour of coal blends was influenced by several properties of individual coals and cannot be estimated by using any single coal parameter. Carbon structure of coal as well as the interaction of volatile matter of individual coals was found to have a strong influence on the burnout of coal blends. Pet-cokes were generally found to burn with a greater difficulty. Carbon structure of pet-cokes was found to have a significant effect on the burnout such that coal blends with highly ordered pet-coke indicated lower burnout. The study shows that up to 10% of pet coke did not change the burnout of PCI blends significantly. As far as combustion is concerned, the drop tube furnace test provides a reasonable distinction of the effect of coal properties for PCI application.

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