In this diploma thesis is processed theoretical analysis of moisture and deformation field of wooden beams. This analysis is used in calculating internal stresses and deformations in model examples using finite element method software. The work is divided according to the types of boundary conditions of the modeled wooden element into three basic groups according to the type of support. The aim of this work was to investigate the influence of moisture load on deformations in the cross-section of a wooden element. Simultaneously with the numerical computation using the software, analytical calculations of deflection were performed for the validation of numerical methods, butt only for the case of force loading without the influence of the humidity gradient.

This thesis describes the temperature field in the envelope wooden structures with regard to possible ways of mounting hole fillings. Furthermore, in this work we can find a description of the propagation of heat in the building structure. The challenge is to create a 2-D models of the selected design solutions for the mounting hole fillings in the envelope wooden buildings. Numerical simulation is performed in a computer software based on the finite element method under the given boundary conditions. The emphasis is on comparing the results of numerical simulations for two design solutions fitting windows using the same track of the structure. In conclusion, the results for both design solutions compared and evaluated.

Emerging "Structure-from-Motion" (SfM) photogrammetry techniques encourage faster, cheaper, and more accessible field methods for accurately reconstructing 3D topography. The SfM method consists of collecting sets of overlapping images of the ground surface with a point and shoot camera, and reconstructing surface topography from the images with developed software programs. This research develops and implements a SfM image acquisition method and post-processing workflow as a supplemental technique to the traditional total-station method to aid in monitoring sandbar change in Marble and Grand Canyons along the Colorado River in Arizona. Due to permitting in Grand Canyon National Park, a 4.9 m pole-mounted camera platform was used in this research to mimic the ground perspective of an aerial platform. This research presents an improved understanding of how the low-angle, pole-mounted camera platform affects image acquisition and ultimately 3D reconstructions of the surface topography. Models of ground surfaces always contain some degree of elevation error, or uncertainty. As such, elevation error models are needed to distinguish whether observed changes to topographic features (in this case sandbars) are real or simply due to elevation error. There are many ways to quantify multiple sources of elevation uncertainty, but in this study the sources of elevation uncertainty were considered to vary across the surface and were characterized accordingly. Especially in river environments with complex surface topography (e.g. steep cut banks), and roughness (e.g. vegetation), quantifying the spatially variable elevation uncertainty of the surface representation is critical for interpreting actual changes in surface topography over repeat surveys. This research: used the sandbar images collected in Marble and Grand Canyons with the pole-mounted camera platform to generate SfM, topographic models; calculated spatially variable surface uncertainty derived from slope and roughness using multiple statistical analyses; built an error model that was calibrated based upon the statistical analyses of the spatially variable surface uncertainty; Key findings of this research are: Densely vegetated topography results in high amounts of elevation uncertainty, and without additional information of the surface underlying the vegetation, the SfM tool is less operational in these areas; Bare, exposed topography with low to high slopes that are not covered in black shadows result in lower surface uncertainty, and are areas where SfM is an operational tool for studies of surface change. Complementing existing topographic sampling methods with more efficient and cost- effective SfM approaches will contribute to the understanding of changing responses of the topographic features. In addition, the development and implementation of SfM and corresponding amounts of elevation uncertainty for monitoring geomorphic change will provide a methodological foundation for extending the approach to other geomorphic systems world- wide.

Terrestrial iron oxides, such as hematite, goethite and magnetite, form specifically cemented concretions in sandstones using an aqueous diagenetic solution. According to the new results, the timeline on which concretions are formed could be much larger than current estimates. The basis for this claim is a magnetic record of the Jurassic Navajo Sandstone in Utah. The record contains fluctuations of remanent magnetization, which could prove the inversion of the Earth's magnetic field. This observation suggests that the time axis of the accumulation of iron concretions is comparable to the time axis of the accumulation of marine iron-manganese nodules, which contain a complex magnetic record. The occurrence of extremely slow changes in iron deposition in sandstones also helps to better understand the origin of concretions. In addition, terrestrial concretions provide an analogy for the "blueberries" found by the Mars rover Opportunity on Mars. These concretions probably underwent similar formation processes and could record inversions of the early magnetic dynamo on Mars.

This master thesis deals with conics in the real projective plane. The goal was to com- prehensibly introduce conics in the projective plane to high-school students and teachers. In order to fulfill this goal, the projective plane and homogenous coordinates were intro- duced, and harmonic set and priniple of duality were studied closely. The conics in the projective plane were approached from the perspective of history, and various definitions. Well-motivated introduction of a pole and a polar was emphasized.

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The totem pole PFC suffers from the Mosfet body diode reverse recovery issue which limits this topology adopted in the CCM high power condition. As the ultra-fast IGBT which is capable of providing 100 kHz switching frequency is available in the market, it is possible to apply the totem pole PFC in CCM high power condition. The thesis provides a method by implementing the ultra-fast IGBT and SiC diode to replace the MOSFET in this topology. To verify the method, a universal CCM totem pole PFC is designed and tested. The design adopts the ADP1048 programmable digital PFC controller by adding external logic gate for totem-pole PFC. ADP1048 greatly simplifies the design process and satisfies the design requirements. The experiment results verify that the totem-pole PFC can be applied into CCM high power condition by using the method. The DC output voltage is well regulated. The power factor is higher than 0.98 when the load is above 400W. The measured efficiency can achieve up to 96.8% at low line and 98.2% at high line condition with switching frequency 80 kHz. / Master of Science