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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.
21

Jiří Olivier Wallis v síti rodinných vztahů / George Olivier Wallis in the network of family relationships

ŘEZÁČOVÁ, Monika January 2018 (has links)
The presented thesis deals mainly with the informative value of the correspondence of the early modern nobleman and the warrior George Olivier Wallis with his family members at the end of the 17th and the first half of the 18th century. The attention of the author will be focus on the extent of the intensity of the relationship between the individual actors of written communication and the image of thought of George Olivier in the letters of close relatives. Last but not least, the thesis also deals with some of the anthropological categories of early modern culture, which appeared on the pages of the letters of Count Wallis and his family members.
22

Private Rechte an kulturunfähigem Land : unter besonderer Berücksichtigung der Rechtslage im Kanton Wallis /

Pfammatter, Aron. January 2009 (has links) (PDF)
Diss. Univ. Bern, 2008. / Ed. commerciale de la thèse de Bern, 2008. Bibliogr.
23

Two-phase flow experiments in a model of the hot leg of a pressurised water reactor

Seidel, T., Beyer, M. 14 March 2012 (has links) (PDF)
In order to investigate the two-phase flow behaviour in a complex reactor-typical geometry and to supply suitable data for CFD code validation, a model of the hot leg of a pressurised water reactor was built at FZD. The hot leg model is operated in the pressure chamber of the TOPFLOW test facility, which is used to perform high-pressure experiments under pressure equilibrium with the inside atmosphere of the chamber. This technique makes it possible to visualise the two-phase flow through large windows, also at reactor-typical pressure levels. In order to optimise the optical observation possibilities, the test section was designed with a rectangular cross-section. Experiments were performed with air and water at 1.5 and 3.0 bar at room temperature as well as with steam and water at 15, 30 and 50 bar and the corresponding saturation temperature (i.e. up to 264°C). The total of 194 runs are divided into 4 types of experiments covering stationary co-current flow, counter-current flow, flow without water circulation and transient counter-current flow limitation (CCFL) experiments. This report provides a detailed documentation of the experiments including information on the experimental setup, experimental procedure, test matrix and on the calibration of the measuring devices. The available data is described and data sheets were arranged for each experiment in order to give an overview of the most important parameters. For the cocurrent flow experiments, water level histograms were arranged and used to characterise the flow in the hot leg. In fact, the form of the probability distribution was found to be sensitive to the boundary conditions and, therefore, is useful for the CFD comparison. Furthermore, the flooding characteristics of the hot leg model plotted in terms of the classical Wallis parameter or Kutateladze number were found to fail to properly correlate the data of the air/water and steam/water series. Therefore, a modified Wallis parameter is proposed, which takes the effect of viscosity into account.
24

Comparing Welch's ANOVA, a Kruskal-Wallis test and traditional ANOVA in case of Heterogeneity of Variance

Liu, Hangcheng 01 January 2015 (has links)
Analysis of variance (ANOVA) is a robust test against the normality assumption, but it may be inappropriate when the assumption of homogeneity of variance has been violated. Welch ANOVA and the Kruskal-Wallis test (a non-parametric method) can be applicable for this case. In this study we compare the three methods in empirical type I error rate and power, when heterogeneity of variance occurs and find out which method is the most suitable with which cases including balanced/unbalanced, small/large sample size, and/or with normal/non-normal distributions.
25

The Reliability Analysis of Mystery Shoppers Examining the Service Quality of a Cram School in Southern Taiwan

Chen, Yuen-yu 07 September 2011 (has links)
More retail and service firms are using mystery shoppers in Taiwan to monitor their frontline operations and to assess their customer service, since the concern over whether their customers are truly satisfied is increasing. However, virtually nothing is known about whether the quality of the data collected by professional mystery shoppers is different or more reliable than that of shoppers disguised by general customers. Here we use a traditional statistics approach to assess the quality of data collected from both professional mystery shoppers and general customers. Feedback questionnaires from general customers and the potential use of mystery shoppers are made as a means of evaluating the service quality of cram schools in Taiwan. The purpose of this thesis is to show that the reliability of mystery shopping data made from professional mystery shoppers is higher than that of data made from general customers. With this question in mind, we conducted a two-step empirical research, as the amount of samples needed was insufficient. First, a primary study to examine the equality of population among branches was carried out in order to pool data from different branches. Then, the relative reliability of the surveys of mystery shoppers to general customers was examined by pooling data of the branches together. The findings provide evidence to suggest that reliable information could be obtained by pooling both shopper reports together. This empirical result also implied that well-trained mystery shoppers can make more objective observations and more effective assessments than general customers.
26

Two-phase flow experiments in a model of the hot leg of a pressurised water reactor

Seidel, Tobias, Vallée, Christoph, Lucas, Dirk, Beyer, Matthias, Deen, Darlianto 26 August 2010 (has links) (PDF)
In order to investigate the two-phase flow behaviour in a complex reactor-typical geometry and to supply suitable data for CFD code validation, a model of the hot leg of a pressurised water reactor was built at FZD. The hot leg model is operated in the pressure chamber of the TOPFLOW test facility, which is used to perform high-pressure experiments under pressure equilibrium with the inside atmosphere of the chamber. This technique makes it possible to visualise the two-phase flow through large windows, also at reactor-typical pressure levels. In order to optimise the optical observation possibilities, the test section was designed with a rectangular cross-section. Experiments were performed with air and water at 1.5 and 3.0 bar at room temperature as well as with steam and water at 15, 30 and 50 bar and the corresponding saturation temperature (i.e. up to 264°C). The total of 194 runs are divided into 4 types of experiments covering stationary co-current flow, counter-current flow, flow without water circulation and transient counter-current flow limitation (CCFL) experiments. This report provides a detailed documentation of the experiments including information on the experimental setup, experimental procedure, test matrix and on the calibration of the measuring devices. The available data is described and data sheets were arranged for each experiment in order to give an overview of the most important parameters. For the cocurrent flow experiments, water level histograms were arranged and used to characterise the flow in the hot leg. In fact, the form of the probability distribution was found to be sensitive to the boundary conditions and, therefore, is useful for the CFD comparison. Furthermore, the flooding characteristics of the hot leg model plotted in terms of the classical Wallis parameter or Kutateladze number were found to fail to properly correlate the data of the air/water and steam/water series. Therefore, a modified Wallis parameter is proposed, which takes the effect of viscosity into account.
27

Web-based highway maintenance functions prioritizing system using analytical hierarchy process

Liu, Jin, master of science in engineering 30 October 2012 (has links)
The Texas Department of Transportation has been experiencing maintenance budget fluctuations recently. The shortage of budget has a negative impact on the agency’s maintenance strategies and results in the undesirable deterioration of highway conditions increasing the risk towards both road users and the agency. This paper aims at developing a methodology to minimize the impact of budget fluctuation by quantifying the risk of not performing a maintenance activity and identifying the priority of maintenance activities based on the quantified risk. With the help of maintenance experts from TxDOT, four maintenance objectives and 16 maintenance function groups were identified and a hierarchy structure was developed based on the objectives and function groups. Four pilot districts were selected to represent the different demographic and climatic regions in Texas and maintenance experts were selected from the four districts to participate in the workshop. The Overall Relative Weights of 16 maintenance function groups were determined based on the individual evaluator’s judgments using the Analytical Hierarchy Process. To determine if the four pilot districts give different relative importance to the four defined objectives and different priority to the 16 maintenance groups, statistical analyses were conducted with the four sets of values, one for each of the four pilot districts, using Kruskal-Wallis test. At last, a web-based prototype system was developed to assist users in generating the list of maintenance projects under budget constraints. Exposure factors, ADT and truck volume, were applied in the system to factor in the impact of traffic to the maintenance strategy. Users of this system can choose to use the weights and parameter values from one of the pilot districts which they think is most comparable to their own district or the state average values that has been proved to be applicable to all the districts in Texas. / text
28

Geomorphological dating of scarps in temperate climate using a modified diffusion model

Oemisch, Mamke. Unknown Date (has links) (PDF)
University, Diss., 2004--Bonn.
29

Learning potential and academic literacy tests as predictors of academic performance for engineering students

Logie, Monica 16 February 2012 (has links)
The aim of this study was to evaluate a battery of tests to be used as part of the process of selecting bursary students for engineering at tertiary institutions. Due to the problems in the schooling system it is not conclusive that all students who have obtained their senior certificates are prepared and able to meet the demands and challenges of tertiary education. The purpose of this study was to determine the criterion related validity of a mathematic proficiency test, Learning Potential Computerised Adaptive Test (LPCAT) and English Literacy Skills Assessment (ELSA) as predictors of academic performance. A quantitative approach was used for the purpose of this study. More specifically the Ex post facto analyses/design is used in this study. The relationships between the dependent and independent variables were determined. Correlation analyses, Kruskal-Wallis test and regression analysis were used for the purpose of this study. The results indicated that the Mathematical proficiency test was the best predictor of academic success, followed by LPCAT and ELSA. The results of this study indicates that the use of academic literacy and learning potential contribute in selecting the best students. Companies and Universities have long been looking for a predictor or predictors of success for students as they enter tertiary studies. This information has the potential to save companies and universities millions of Rands annually by helping them make better investment decisions. / Dissertation (MCom)--University of Pretoria, 2010. / Human Resource Management / Unrestricted
30

Multivariate analysis and GIS in generating vulnerability map of acid sulfate soils.

Nguyen, Nga January 2015 (has links)
The study employed multi-variate methods to generate vulnerability maps for acid sulfate soils (AS) in the Norrbotten county of Sweden. In this study, the relationships between the reclassified datasets and each biogeochemical element was carefully evaluated with ANOVA Kruskal Wallis and PLS analysis. The sta-tistical results of ANOVA Kruskall-Wallis provided us a useful knowledge of the relationships of the preliminary vulnerability ranks in the classified datasets ver-sus the amount of each biogeochemical element. Then, the statistical knowledge and expert knowledge were used to generate the final vulnerability ranks of AS soils in the classified datasets which were the input independent variables in PLS analyses. The results of Kruskal-Wallis one way ANOVA and PLS analyses showed a strong correlation of the higher levels total Cu2+, Ni2+ and S to the higher vulnerability ranks in the classified datasets. Hence, total Cu2+, Ni2+ and S were chosen as the dependent variables for further PLS analyses. In particular, the Variable Importance in the Projection (VIP) value of each classified dataset was standardized to generate its weight. Vulnerability map of AS soil was a result of a lineal combination of the standardized values in the classified dataset and its weight. Seven weight sets were formed from either uni-variate or multi-variate PLS analyses. Accuracy tests were done by testing the classification of measured pH values of 74 soil profiles with different vulnerability maps and evaluating the areas that were not the AS soil within the groups of medium to high AS soil probability in the land-cover and soil-type datasets. In comparison to the other weight sets, the weight set of multi-variate PLS analysis of the matrix of total Ni2+& S or total Cu2+& S had the robust predictive performance. Sensitivity anal-ysis was done in the weight set of total Ni2+& S, and the results of sensitivity analyses showed that the availability of ditches, and the change in the terrain sur-faces, the altitude level, and the slope had a high influence to the vulnerability map of AS soils. The study showed that using multivariate analysis was a very good approach methodology for predicting the probability of acid sulfate soil.

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