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<p>This thesis investigates the effects of sample preparation methods, which has substantial influence on the internal structure or fabric of the sample, and interparticle locking on the behaviour of sand through experimental study. Extensive laboratory tests were conducted on two sands (namely, Ottawa sand and crushed limestone) with distinct particle shape and surface texture, using a Bishop-type triaxial testing system.</p><p>A total of eight sample preparation methods were used to fabricate specimens with different initial fabric, with specimens being fabricated using water pluviation, moist tamping, and moist rodding. The experimental data reveal that sample preparation methods have significant effect on both deformation characteristics and shear strength of sand, in addition to the density and the effective confining pressure applied to the specimens. More specifically, water pluviation and moist tamping tend to yield specimens of high anisotropy and large dilation, which in turn results in higher friction angle in conventional triaxial compression. The effect of sample preparation methods was also observed from undrained tests on saturated sand.</p><p>Laboratory tests on crushed limestone consisting of angular particles demonstrate that strong interparticle locking may develop owing to particle angularity. The shear resistance of sand with angular particles has contributions from interparticle friction, dilatation and interparticle locking. Moreover, interparticle locking, which largely exists at the peak shear resistance of sand but vanishes with dilation at large deformation, exists under both low and high stress levels investigated in this study. A conceptual model was proposed to take into account the energy consumption associated with breaking interparticle locking during deformation when estimating the dilatancy and strength of granular soils.</P><P>The behaviour of sand along proportional strain paths was also investigated, with the focus being placed on strain softening and material instability in the context of Hill's second order work. Depending on the strain path or the deformation history, a dilatant sand displaying hardening and stable behaviour under isochronic (undrained) conditions, which is often used as a reference in soil mechanics, may succumb to unstable flow type behaviour along dilative strain paths. More specifically, when the imposed rate of dilation exceeds the inherent rate of dilation of the material, a dense sand specimen will have flow failure similar to that of a saturated loose specimen subjected to undrained compression. On the other hand, a loose sand may not have a flow failure when it is forced to have contractive volume change along imposed strain paths.</P> / Thesis / Master of Science (MSc)

<p> Photocatalytic TiO2 coated paper was prepared as antibacterial paper to investigate bactericidal activity of TiO2 in the presence of UV light. When TiO2 exposed to UV light, it produced hydroxyl radicals which were strong oxidative groups and could damage the cell wall causing death of bacteria. The goal of this work was to develop a promising method for microbiological examination of antibacterial paper and to test the disinfection properties of photocatalytic TiO2 coated paper after UV illumination.</p> <p> Three different methods were modified to test antibacterial effect of TiO2 coated paper. The disk diffusion method, the washing method, and the membrane filter method. It was found that disk diffusion technique would not work because of insolubility of TiO2 in water but it could be used for any other antibacterial paper that consisted water soluble agent. The results from membrane filter method agreed with those of washing method showing the reduction of E.coli colonies for TiO2 coated paper after exposure to UV, comparing to blank paper.</p> <p> With use of washing method, it was shown that by changing some functions such as: increasing TiO2 content on the paper, increasing UV irradiation time or UV intensity, survival ratio of the bacteria decreased.</p> / Thesis / Master of Applied Science (MASc)

This study addresses a usability testing method and the development of a new testing procedure that includes eye-tracking. By correcting errors within the system before it reaches the end-user contributes to satisfied customers, high quality, and a useful system. Testing is all-important in identifying errors in the test procedure to be sure to capture issues in the system being tested. The aim of the thesis is to analyze and examine the testing methods used in the company and present how the development of a new testing method should be suitable for the company. The traditional testing method is compared with a new testing method that includes eye-tracking. The empirical material was generated by usability testing. Other methods such as background questionnaire, observation, interview, review thinking-aloud, and pilot test were also used. In the conclusion of the study, it was found that the traditional testing method met the criteria of how a usability test should be conducted. Another conclusion was that the new testing method helps to clearly see and identify usability problems that may be present in a system. / Denna studie behandlar en testmetod för användbarhet och vikten av att ta fram en ny utvecklad testmetod med hjälp av eye-tracking. Genom att korrigera fel inom systemet innan det når fram till slutanvändaren bidrar nöjda kunder, hög kvalitet och ett användbart system. Syftet med uppsatsen är att analysera och utreda testmetoder som används i företaget samt kartlägga hur utvecklingen av en ny testmetod ska vara passande till verksamheten. Detta jämför jag med den nuvarande testmetoden med implementering av eye-tracking. Uppsatsens undersökningsfrågor är således: Hur kan företagets nuvarande testmetod förbättras? Hur lätt är det för företaget att använda den nya testmetoden? Är den nya testmetoden mer användbar för företaget jämfört med deras nuvarande metod? Det empiriska materialet har framställts genom användbarhetstester. Även andra metoder, såsom bakgrundsenkät, observation, intervju, retrospektiv granskning och pilottest har använts. I studiens slutsats har det framkommit att den nuvarande testmetoden uppnår kriterier på hur en användbarhetstest ska genomföras. Ytterligare slutsats har varit att den nya testmetoden bidrar med att tydligt se och identifiera användbarhetsproblem som kan finnas i ett system.

This diploma thesis analyses the phenomenon of adapting e-shops selling electronics and computers to the Generation Y in the terms of website usability. The theoretical part is divided into three main chapters. The first chapter describes a consumer behavior, shopping behavior and the difference between shopping behavior in physical stores and their cyberspace counterparts. The following chapter deals with the Generation Y and its characteristics. The last part describes the web usability itself, its common flaws in usability and the topic of web usability testing. The practical part is dedicated to a web usability testing on selected e-shops. The testing itself  was conducted by the user testing method, where all the tested subjects belonged to the Generation Y. A questionnaire and a guided interview were also used to gather information for the study. The survey revealed many elemental flaws in the terms of  web usability of studied samples and presented suggestions how to correct them. A big problem was found mainly in the design structure of the sites. Users were under constant advertisement pressure which has neutral or even negative effect on the Generation Y.

This diploma thesis deals with construction and technological survey of the reinforced concrete structure. The first part of the diploma thesis deals with the properties of the reinforced concrete and with the building survey methods applied in the second part of the thesis. The second part of the diploma thesis focuses on diagnostics of existing structure. More specifically, the hardness of the concrete is tested using a Schmidt hammer and then it is further specified by testing the cores. The reinforcement in the reinforced concrete is also tested using electromagnetic indicator, ground-penetrating radar, and chopped probes. Lastly, a static assessment of the selected girder and column is conducted.

Two surface wave testing methods, namely, (i) the spectral analysis of surface waves (SASW), and (ii) the multi-channel analysis of surface waves (MASW), form non-destructive and non-intrusive techniques for predicting the shear wave velocity profile of different layers of ground and pavement. These field testing tools are based on the dispersive characteristics of Rayleigh waves, that is, different frequency components of the surface wave travel at different velocities in layered media. The SASW and MASW testing procedure basically comprises of three different components: (i) field measurements by employing geophones/accelerometers, (ii) generating dispersion plots, and (iii) predicting the shear wave velocity profile based on an inversion analysis. For generating the field dispersion plot, the complexities involved while doing the phase unwrapping calculations for the SASW technique, while performing the spectral calculations on the basis of two receivers’ data, makes it difficult to automate since it requires frequent manual judgment. In the present thesis, a new method, based on the sliding Fourier transform, has been introduced. The proposed method has been noted to be quite accurate, computationally economical and it generally overcomes the difficulties associated with the unwrapping of the phase difference between the two sensors’ data. In this approach, the unwrapping of the phase can be carried out without any manual intervention. As a result, an automation of the entire computational process to generate the dispersion plot becomes feasible. The method has been thoroughly validated by including a number of examples on the basis of surface wave field tests as well as synthetic test data. While obtaining the dispersion image by using the MASW method, three different transformation techniques, namely, (i) the Park’s wavefield transform, (ii) the frequency (f) -wavenumber ( ) transform and (iii) the time intercept ( -phase slowness (p) transform have been utilized for generating the multimodal dispersion plots. The performance of these three different methods has been assessed by using synthetic as well as field data records obtained from a ground site by means of 48 geophones. Two-dimensional as well as three-dimensional dispersion plots were generated. The Park’s wavefield transformation method has been found to be especially advantageous since it neither requires a very high sampling rate nor an inclusion of the zero padding of the data in a wavenumber (distance) domain. In the case of an irregular dispersive media, a proper analysis of the higher modes existing in the dispersion plots becomes essential for predicting the shear wave velocity profile of ground on the basis of surface wave tests. In such cases, the establishment of the predominant mode becomes quite significant. In the current investigation for Rayleigh wave propagation, the predominant mode has been computed by maximizing the normalized vertical displacements along the free surface. Eigenvectors computed from the thin layer approach (TLM) approach are analyzed to predict the corresponding predominant mode. It is noted that the establishment of the predominant mode becomes quite important where only two to six sensors are employed and the governing (predominant) modal dispersion curve is usually observed rather than several multiple modes which can otherwise be identified by using around 24 to 48 multiple sensors. By using the TLM, it is, however, not possible to account for the exact contribution of the elastic half space in the dynamic stiffness matrix (DSM) approach. A method is suggested to incorporate the exact contribution of the elastic half space in the TLM. The numerical formulation is finally framed as a quadratic eigenvalue problem which can be easily solved by using the subroutine polyeig in MATLAB. The dispersion plots were generated for several chosen different ground profiles. The numerical results were found to match quite well with the data available from literature. In order to address all the three different aspects of SASW and MASW techniques, a series of field tests were performed on five different ground sites. The ground vibrations were induced by means of (i) a 65 kg mass dropped freely from a height of 5 m, and (ii) by using a 20 pound sledge hammer. It was found that by using a 65 kg mass dropped from a height of 5 m, for stiffer sites, ground exploration becomes feasible even up to a depth of 50-80 m whereas for the softer sites the exploration depth is reduced to about 30 m. By using a 20 lb sledge hammer, the exploration depth is restricted to only 8-10 m due to its low impact energy. Overall, it is expected that the work reported in the thesis will furnish useful guidelines for (i) performing the SASW and MASW field tests, (ii) generating dispersion plots/images, and (iii) predicting the shear wave velocity profile of the site based on an inversion analysis.

The main theme of this diploma thesis is a building survey and diagnostics of a reinforced concrete construction. In the first, theoretical part the focus lies on a description of each method for testing constructions and their evaluation. The second, practical part focuses mainly on finding of material characteristics and reinforcement of particular parts of the construction. On basis of obtained information, the final part of this paper focuses on static assessment of chosen parts of the construction.