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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.
61

Methodik zur prozessorientierten Restrukturierung von Arbeitssystemen

Schmiedl, Nadja 16 September 2010 (has links)
Die steigende Dynamik sowie der steigende Konkurrenzdruck, dem deutsche und europäische Produktionsunternehmen aufgrund von Individualisierungs- und Globalisierungstendenzen ausgesetzt sind, erfordert neue Konzepte zur Gestaltung effizienter Prozesse und damit konkurrenzfähiger Produkte. Trotz oder gerade wegen eines vielfach hohen Automatisierungsniveaus und der damit verbundenen Komplexität sind viele Arbeitssysteme durch einen hohen Anteil an Personalkosten für technikerhaltende Arbeitsaufgaben geprägt. Die vorliegende Arbeit stellt einen Ansatz vor, wie bestehende automatisierte Arbeitssysteme analysiert, bewertet und bzgl. des Personaleinsatzes optimiert werden können.
62

Characterization and Application of Colloidal Nanocrystalline Materials for Advanced Photovoltaics

Bhandari, Khagendra P. 22 October 2015 (has links)
No description available.
63

Non-Destructive Evaluation of Urethane-Ester Coating Systems Using the Scanning Kelvin Probe Technique

Borth, David J. 31 May 2018 (has links)
No description available.
64

The effect of computer simulations on Grade 12 learners' understanding of concepts in the photoelectric effect / The effect of computer simulations on Grade twelve learners' understanding of concepts in the photoelectric effect

Kunnath, Bobby Joseph 12 1900 (has links)
The study investigated the impact of computer simulations on the teaching and learning of photoelectric effect in Grade 12. The Grade 12 Physical Sciences curriculum has components of physics and chemistry. The photoelectric effect is a section in the physics curriculum and examination in the National Senior Certificate. In this case study, thirty learners were randomly divided into three groups in one rural school in the Frances Baard district in the Northern Cape Province. A randomised pre-test - post-test control group design was implemented. Data were collected through pre and post tests, by observation of the lessons and learner interviews. An analysis of variance performed showed that there was no significant difference on pre-test scores for the three groups. A paired -sample t-test on the post-test scores discovered that the Teacher-Centred Experimental Group (TCEG) performed better than the Learner-Centred Experimental Group (LCEG); (t statics, t (9) = -6.135, p < 0.05). In addition, the Control Group (CG) where the teacher used the traditional method of teaching performed even better than the Learner-Centred Experimental group. An analysis of covariance on the post-test scores with learners' pre-test scores as the covariate showed a significant effect on the instructional group favouring the TCEG (F (2,29) = 52.763, p < 0.05). The Hake's normalised gain, <g> was used to measure the effectiveness of the intervention. The normalised gain showed a high-g (0.794) for the TCEG, a medium-g (0.405) for the CG and a low-g (0.134) for the LCEG. The interview data also confirms that the TCEG learners benefited more than the LCEG learners. It is, therefore, suggested that the TCEG approach is a better method for the effective teaching of photoelectric effect. / Science and Technology Education / M. Sc. (MSTE)
65

Visualisation of Local Charge Densities with Kelvin Probe Force Microscopy

Milde, Peter 10 June 2011 (has links)
For the past decades, Kelvin probe force microscopy (KPFM) developed from a sidebranch of atomic force microscopy to a widely used standard technique. It allows to measure electrostatic potentials on any type of sample material with an unprecedented spatial resolution. While the technical aspects of the method are well understood, the interpretation of measured data remains object of intense research. This thesis intends to prove an advanced view on how sample systems which are typical for ultrahigh resolution imaging, such as organic molecular submonolayers on metals, can be quantitavily analysed with the differential charge density model. In the first part a brief introduction into the Kelvin probe experiment and atomic force microscopy is given. A short review of the theoretical background of the technique is presented. Following, the differential charge density model is introduced, which is used to further explain the origin of contrast in Kelvin probe force microscopy. Physical effects, which cause the occurence of local differential charge densities, are reviewed for several sample systems that are of interest in high resolution atomic force microscopy. Experimental evidence for these effects is presented in the second part. Atomic force microscopy was used for in situ studies of a variety of sample systems ranging from pristine metal surfaces over monolayer organic adsorbates on metals to ferroelectric substrates both, with and without organic thin film coverage. As the result from these studies, it is shown that the differential charge density model accurately describes the experimentally observed potential contrasts. This implies an inherent disparity of the measurement results between the different Kelvin probe force microscopy techniques; a point which had been overseen so far in the discussion of experimental data. Especially for the case of laterally strong confined differential charge densities, the results show the opportunity as well as the necessity to explain experimental data with a combination of ab initio calculations of the differential charge density and an electrostatic model of the tip-sample interaction.

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