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1. 1. Well Testing, Methods and Applicability

   Författare :Jan-Erik Rosberg; Teknisk geologi; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; slug tests; well completion; re-injection; Well testing; pumping tests; injection tests; well development; pneumatic initiation; hydro-jetting; coiled tubing; tunnel lining; deep wells;

   Sammanfattning : Well testing is widely used today in water wells, oil and gas wells, for geothermal applications, within civil engineering projects, thermal storage and CO2 storage. The overall testing goal is to verify the productivity from a well and/or for characterization of hydraulic and thermal properties, as well as the spatial limitations of an aquifer. LÄS MER

3. 2. Tests of random effects in linear and non-linear models

   Författare :Erling Häggström Lundevaller; Umeå universitet; []
   Nyckelord :Random effects; score test; NLS; heteroskedasticity; measurement error; Poisson regression; trip frequencies; Statistics; statistik;

   Sammanfattning : .... LÄS MER

4. 3. Performance of Stress-Laminated-Timber Bridge Decks

   Författare :Kristoffer K J Ekholm; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; butt joints; non-linear modelling; stress-laminated timber; linear modelling; prestressing; timber bridges; interlaminar slip; FE modelling; laboratory tests; durability;

   Sammanfattning : Stress-laminated-timber (SLT) bridge decks are a satisfactory alternative to conventional short-span bridges in terms of cost and performance. SLT decks are made from a number of timber or glulam beams positioned side by side and stressed together using high-strength steel bars. LÄS MER

5. 4. Rank Estimation in Elliptical Models : Estimation of Structured Rank Covariance Matrices and Asymptotics for Heteroscedastic Linear Regression

   Författare :Kristi Kuljus; Silvelyn Zwanzig; Dietrich von Rosen; Jana Jureckova; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; elliptical distributions; multivariate ranks; rank covariance matrix; linear rank regression; heteroscedastic errors; linear rank statistics; Mathematical statistics; Matematisk statistik;

   Sammanfattning : This thesis deals with univariate and multivariate rank methods in making statistical inference. It is assumed that the underlying distributions belong to the class of elliptical distributions. LÄS MER

7. 5. Contributions to generalized Wilcoxon rank tests

   Författare :Marie-Louise Öhman; Hans Nyquist; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Censored data rank sum tests; Gehan s test; Generalized Wilcoxon test; Jackknifing; Two sample problem; Simulation; Survival data; Variance estimation; Influence function; Gross error sensitivity; Sensitivity curve; Misclassification; Statistics; computer and systems science; Statistik; data- och systemvetenskap; Statistics; statistik;

   Sammanfattning : In unbalanced small sample size problems with right censorings, the variance estmators of linear rank statistics, may be biased. This is the case with the commonly applied variance estimators for the generalized Wilcoxon rank test statistics of Gehan and Prentice. LÄS MER