The thesis presents a systematic experimental and numerical study on the interactions among porous fence, airflow, and windblown snowdrifts, a knowledge that will contribute to optimize the performance of porous wind shielding system in Cold Regions. A comprehensive review of the concepts, theories, techniques, and key findings associated with the research work has been undertaken. The key technical parameters influencing fence performance have been systematically studied by means of wind tunnel experimental investigations and Computational Fluid Dynamics (CFD) simulations. The study has found that porosity is the most influential structural parameter affecting the performance of porous fences in many aspects. Fence height stands a significant positive position in terms of its performance. It was found that fence performance is not sensitive to the changes of approaching atmospheric airflow velocity. Nevertheless, a bottom gap can improve snow fence trap efficiency. All of those findings agree with most of the findings of other researchers, which affirms that the research methodology adopted in this research is sound. Physical experimental work was performed to assess the reliability and credibility of the numerical models. Those models have been intentionally simplified, which made them easier to construct and quicker to obtain numerical solutions at a lower computational cost. Furthermore, the numerical models demonstrate the level of competence acquired through this research that is implemented in the optimisation of fence design. Special attention has been paid to the issues where elaborate research work has not been systematically reached in the open literature, this includes areas such as the effects of arrangement of porous holes, fence surface shear, and directions of wind load with respect to the fence, etc. Correlation between the reattachment length, the shelter distance, and the creation and distribution of fence surface shear is reported, to the author's knowledge, for the first time in the open literature. General guidelines for the design of shelters based on porous fences have been established through this study. For example, the desirable size of hole range should be identified beforehand, and porous holes with sharp angular corners should usually be avoided in the fence design. It is recommended to place the fence within an angle of 30° to the wind load, where the effective shelter distance can be estimated in a linearized equation, and the normal drag coefficient can be described as a function of cos2θ. Optimal design of the arrangement of porous holes will maximize the fence performance, especially when the close fence environment is of concern. Although the definition of fence effective zone is still vague in the research field, the key factors influencing the fence effective zone have been investigated by evaluating the reduction of wind velocity leeward of the fence in this thesis. It is found that the fence effective zone is not sensitive to the change of approaching airflow velocity, and that increasing fence height will increase the physical size of the fence effective zone, but not in a proportional manner. It is also concluded that fence effective zone will be significantly reduced when the non-normal wind load is inclined at an angle greater than 30° to the fence. The effective zone increases effectively when the fence porosity is optimal. In contrast to the majority of published research work, the transient snow transport model presented in this work considers the snow transport rate as a whole without distinguishing the rate in saltation and suspension layer. The numerical study indicated that the position of the snow crest is mainly determined by the fence height, while porosity and bottom gap mainly affect the downwind deposition length. The optimal porosity for snow fences is in the range of 0.4 to 0.5, which is greater than the one for wind fences, which lies in the range from 0.25 to 0.35. Two snow crests have been observed leeward the fence at the onset of snow deposition, when the fence was placed without a bottom gap to the snow ground. This finding has not been encountered in any of the reported research work. Wind tunnel simulations of snowdrift around the fences have marginally under-predicted the sizes of snow deposition. The numerical predictions were quantitatively and qualitatively in good agreement with the field observations. This incompetence of wind tunnel experiments on porous fences implies that numerical modelling can play a more important role in snow fence research.

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The geographic variation of taxonomic richness may be directly determined by climate through contemporaneous/ecological processes, versus other (e.g., historical/evolutionary processes) that happen to be collinear with contemporaneous climate. In Chapter 1 I evaluated hypotheses from both groups of explanations in North America. If contemporaneous climate controls patterns of richness, then richness should vary with climate through time in the same way that richness varies with current climate through space. Over the last ca. 11,000 yr, richness-temperature relationships remained reasonably constant. Between 12,000 and 14,000 yr BP, when climate fluctuated rapidly, richness gradients as a function of temperature were significantly shallower. If historical climate over the last 21,000 years determines patterns of richness, then historical climate should be a better predictor of richness than contemporaneous climate. I rejected historical-climate as a better predictor of richness. Contemporaneous climate stands as the most plausible explanation for contemporaneous patterns of richness, at least over the last 11,000 yr. In Chapter two, I tested the prediction that richness of most taxa should increase with temperature in all but the warmest and driest areas. Climate warming during Pleistocene-Holocene transition led richness increases in wet areas, but richness declines in dry regions, as expected from current richness-climate relationships. A decline in small mammal species richness in Northern California since the late Pleistocene was expected from the current richness-climate relationship for this group in North America. These results contest the view that future global warming may lead to species extinction rates that would qualify as the sixth mass extinction in the history of the earth. In chapter three, I first tested the hypothesis that richness gradients mainly reflect the sum of individual species climatic tolerances. I tested this hypothesis for birds, mammals and trees native to eastern North America (ENA, where there are no major barriers to dispersal). The number of species present in any given area in ENA is usually much smaller than the number of species in the continental pool that tolerate the climatic conditions in that area. Second, I tested several explanations for patterns of unfilled potential richness. Unfilled potential richness is inconsistent with postglacial dispersal lags, climatic variability since the Last Glacial Maximum, or with biotic interactions. In contrast, unfilled richness is highly consistent with a probabilistic model of species climate occupancy. Individual species climatic tolerances is not the process generating the main current patterns of richness, nor are post-glacial dispersal lags, climatic variability since the LGM or biotic interactions. This thesis is consistent with the hypothesis that contemporaneous climate directly controls spatial patterns of richness. Generally, there seems to be little need to invoke historical processes as determinants of current gradients of richness.

Using two experiments, where children either rolled dice or solved a matrix task, we examined whether scouts are more honest than non-scouts. In the first experiment, participants completed a matrix task. The papers were then shredded, and participants self-reported the number they had correctly solved. After analysing the results, we found that 10.81 % of scouts and 13.04 % of non-scouts lied. This difference, between the honesty of scouts and non-scouts, was not statistically significant. There was no perceived effect from being scout on the individual's honesty, as well as from taking the scout promise, or years of experience in a scout organization on the scout's honesty. In the second experiment, participants rolled the dice privately. According to value rolled, participants could either take (1, 2, 3), or leave (4, 5, 6), a Kinder chocolate reward. Statistically, participants would be expected to take the reward 50 % of the time. This was the case for the scouts group, the results did not differ statistically from 50:50, but not for the non-scouts. However, the difference between scouts and non-scouts was not statistically significant, indicating that there is no significant difference in honesty between scouts and non-scouts. Thus, our hypothesis that scouts are more honest than non-scouts was not supported.

On s'intéresse à la fragmentation d'objets cohésifs au travers d'un ensemble d'expériences modèles. Dans une première expérience, on force l'extension radiale d'un anneau formé de grains cohésifs (billes magnétiques ou billes de polymères liées par des ponts liquides). Sous l'effet de l'extension, les grains se séparent, puis, à cause de la cohésion, ils entament une dynamique d'agrégation qui conduit à la formation de fragments de tailles diverses. On montre que la distribution des tailles de fragments ainsi formés converge vers une loi de distribution Gamma et on propose un modèle expliquant l'évolution auto-similaire de la distribution. Dans un deuxième temps, on introduit une distribution d'intensité des liaisons entre les grains. La fragmentation en présence de ces "défauts" conduit à une distribution des tailles de fragments plus large, mais dont la loi est conservée. Dans une dernière étude, une coque sphérique composée de liquide est forcée à s'étendre par la combustion d'un mélange de gaz réactif emprisonné à l'intérieur de celle-ci. La distribution des tailles des gouttes qui en résulte obéit à la même famille de lois de distribution que celles observées pour les anneaux composés de grains cohésifs. Dans cette dernière expérience, le rôle des défauts est joué par les instabilités hydrodynamiques se développant sur la surface de la coque liquide au cours de son extension. Ainsi la largeur de la distribution des tailles de gouttes dépend de la vigueur de l'extension de la coque liquide. / We are studying the fragmentation of cohesive objects through a set of model experiments. In a first experiment, we force the radial extension of a ring made of cohesive grains (magnetic beads or polymer beads bonded with liquid bridges). Because of the extension, the grains separate from each other, then, because of the cohesion, start an aggregation dynamic leading to the formation of fragments of different sizes. We show that the distribution of the fragment sizes formed in this way converge to a Gamma law distribution and we propose a model explaining the self-similar evolution of the distribution. On a second part we introduce a distribution of intensities of the bonds between the grains. The fragmentation in the presence of "defects" leads to a broader size distribution, with the same law. In a last study, a spherical shell composed with liquid is forced to extend by the combustion of a reagent mixture of gas confined inside. The drop size distribution observed is conform to the same family of distribution laws found for the rings composed with cohesive grains. In this last experiment the role of defects is played by the hydrodynamic instabilities developing on the surface of the liquid shell under extension. Thus the broadness of the drop size distribution depends on the strength of extension of the liquid shell.

Master´s Thesis aims to find the answer to the question whether subliminal advertising is able to influence consumer behaviour and make him to choose the specific product. The first, theoretical part, deals with literature review which focuses on the issue of subliminal advertising. In the second and third part, it concentrates on the description of methodology used in studies of aforementioned topic and definition of statistical methods used for evaluating the experiment. The practical part of the Master´s Thesis concentrates on realisation of the experiment verifying the effects of subliminal advertising. The purpose of the experiment was to determine if pictorial subliminal priming of bottle of specific brand of mineral water is able to influence the choice of consumer. Experiment was conducted on students of University of Economics, Prague and consisted of subliminal priming of participants by Poděbradka bottle. Afterwards it was investigated whether participants, opposed to those who were not subliminally primed, chose subliminally primed mineral water in the higher extent. The experiment determined that subliminal advertising of brand of specific mineral water did not affected the choice of participants and their intention to drink this mineral water. At the end, Master´s Thesis indicates limitations of conducted experiment and recommends alignment for the future research.

Concrete-Filled Steel Tubular (CFST) columns are increasingly being used because of their many advantages, including high strength, high ductility, and higher fire resistance than conventional steel or concrete columns of the same size. In order to maximise the advantages of CFST column, composite action of the column should be ensured. In realistic structures, the load is not directly applied to the entire CFST column section and is introduced from the beam-column connection. Simple shear connections, which are usually preferred in constructions, are only connected to the external face of the steel tube and there is an issue about how this load is introduced to the concrete core, through the bond at the steel/concrete interface. There are fundamental errors in the load introduction mechanism assumed in various current design methods. Furthermore, based on this erroneous load introduction mechanism, construction methods, such as placing shear connectors inside the steel tube or using through-column plates, are recommended to ensure complete load introduction. However, these methods are either impractical or uneconomical. The aim of this project, therefore, is to develop a thorough understanding of the load introduction mechanism and to use the new insights to assess design implications, for both ambient temperature and fire safety design. The research has been conducted through physical testing, extensive numerical modelling and detailed analytical derivations. A series of new load introduction tests, in which square CFST columns are loaded through simple fin plate connections, are carried out. These tests are designed to investigate the effects of changing column lengths below and above the connection, the effectiveness of using shear connectors inside the steel tube below the connection (according to Eurocode 4) and using a cap plate on the column top for load introduction into the concrete core. The test results indicate that the connection load is introduced to the concrete core through the column length above and within the connection or the cap plate on top of the column. This is different from the currently assumed mechanism of load introduction which assumes that load introduction occurs from underneath the connection. Below the connection, there is transfer of forces from the steel tube to the concrete core, but the total force in the column remains unchanged. Consequently, using shear connectors below the connection is ineffective in increasing CFST column strength, as has been demonstrated by the tests. The physical tests are supplemented by an extensive numerical parametric study to check whether the conclusions are applicable to different design conditions and to provide data for development of a new design method. The parameters include: section geometry (square, circular, and rectangular), position of load application to CFST column, dimensions of the square column cross-section, steel tube thickness, connection length, column length above the connection, column length below the connection, and maximum bond stress at the steel-concrete interface. The numerical simulation results confirm the experimental observations. Furthermore, the numerical simulation results indicate that the entire column length and the entire perimeter of the steel-concrete interface above and within the connection are engaged in load introduction. Based on the experimental and numerical simulation results, a simple calculation method has been proposed to calculate the column cross-section resistance under compression. According to this equation, the concrete compression resistance to the composite column is the minimum of the plastic resistance or the bond strength within and above the connection. This gives rise to a “concrete strength reduction factor” to account for incomplete load introduction, being the ratio of the load introduced to the concrete core through the interface bond to the concrete plastic resistance. Based on the new load introduction calculation method and using representative values of column dimensions and concrete cylinder strength, it has been demonstrated that complete load introduction can be achieved in almost all practical arrangements of concrete-filled tubular construction. For slender CFST column design, this concrete strength reduction factor should also be used to calculate the CFST column cross-section flexural stiffness. For a CFST column under combined axial compression and bending, the concrete strength reduction factor should be used when calculating the compression force, but should be ignored when calculating the bending resistance because composite action is not necessary for bending of the CFST column. The new load introduction mechanism induces additional compression in the concrete core and possible tension in the steel tube above the connection. Therefore, the concrete core of the column above the connection in multi-storey construction should be designed to resist the additional compression force. For the steel tube, in ambient temperature design, the steel contribution ratio (steel section resistance/plastic resistance of composite cross-section) of the top floor column should be at least 0.25. For fire resistance design, the steel contribution ratio of the top floor columns, those on the floor below the top floor, and those two floors below the top floor, should not be less than 0.5, 0.33, and 0.25 respectively.

Laser technologies have made distinguished contributions to modern industry. These have typically been realised through the important role played by lasers in the advancement of manufacturing technology in many areas such as welding, which has become an important joining technique and thus promoted the use of lasers in a wide variety of applications in the oil, gas, aerospace, aircraft, automotive, electronics and medical industries. A detailed review of previous work in the use of lasers for advanced manufacturing, and in particular, laser beam welding is given. The work reported in this thesis aims to develop a new method of laser welding. This is connected with investigations relating to the production of net shape welds for bead-on-plate welding and butt welding of mild steel plates. Based on the nature of its operation, use of a fibre laser was considered most suitable compared to other solid state lasers. Net-shape welds were demonstrated on mild steel plates using an IPG 1 kW single mode fibre laser with a maximum power output of 1000 W.The thesis shows results from experimental and modelling (based on finite element and computational fluid dynamic modelling) to validate the idea and the understanding of underlying scientific principles. The thesis is presented in the form of a collection of published work generated by the author during the course of this project. In addition, some results that are not yet published are also included. Design of experiments and statistical modelling has been used in the experimental work to understand the process parameter interactions. Microstructural and mechanical testing have been carried out to evaluate the performance of the welds. Net shaped (the weld bead is flat to the parent material surface) welds have been achieved and compared with standard welds. The understanding of net-shape weld formation and the effect of the laser welding parameters was enhanced by the theoretical modelling. The thesis concludes with a summary of scientific findings and an overview of future work.

This thesis examines the possibility of retaining, redesigning, and integrating existing farm and forestlands within the proposed South Campus community development at the University of British Columbia (UBC). The central tenant of my thesis is, given the importance of agriculture in the development of human culture and the UBC Point Grey Campus, and the vital role it will play in the 21st Century, agricultural lands and facilities should be conserved and given a place of importance within the UBC landscape. An explanation is provided on how such an integrative proposal for these lands, collectively known as the UBC South Campus Farm, would support the economic, ecological, and social interests and expectations of the University, and the Greater Vancouver Regional District (GVRD), while providing an exciting learning and living environment for students, faculty staff and community members. An alternative proposal for the South Campus Farm and the South Campus community is provided that supports the stated interests of the University and the GVRD. This is accomplished through a careful assessment of the cultural and biophysical features of the South Campus lands and the subsequent development and application of a regenerative design process applied within a fourfold framework based on the concepts of ecology, economy, integrity and beauty. The final design proposal is compared and evaluated against the current situation and the University development plans. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Graduate

Product placement as one of the modern tools of marketing communication has become very important. This is also the case of the Czech Republic, especially after recent legislative changes and related legalization of product placement. The thesis characterizes product placement, states its particular forms and methods of evaluating its effectiveness. The aim of the thesis is to determine the difference between product placement in a situation when in an audiovisual work is presented in the first case known brand, in the second case unknown brand and in the third case fictitious brand. This is examined by the executed experiment based on watching a video with three type situations and filling in a subsequent questionnaire survey. Analysis of the survey results reveals that product placement is the most effective when displaying known brand, using unknown brand is considerably less effective and that the effectiveness of fictitious brand is the lowest. On the basis of statistical hypothesis testing, it is confirmed that there is a statistically significant relation between brand knowledge and its effectiveness.