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The nature of the inter-relationship of valley-side slopes and the streams at their base is regarded as being of fundamental significance in the study of landscape morphology. One aspect of this relationship, the problem of the development of valley-side asymmetry in east-trending valleys under the joint influence of microclimatic and stream controls, is investigated in two areas of uniform, flat-lying beds, using the approach and techniques of experimental design. Valleys in both study areas have been formed during the last 12,000 years, so that the importance of fossil slope forms is minimal. The variation in lithology between the two areas is held to be of less consequence than the difference in climatic regimes, as far as the type of asymmetry developed. The moister of the two areas, S.W. Manitoba, shows the typical, valley-wide asymmetry regarded as characteristic of non-periglaclal regions, with north-facing slopes significantly steepened by 3.1°, on average: the effects of basal steepening by meandering streams are additive with the microclimatic differences. In the drier area, S.E. Wyoming, the effects of the two controls are non-additive, and asymmetry is a purely localised development created by the over-steepening of shaded, north-facing undercut slopes. The moisture availability in this environment is probably increased by the formation of snowdrifts in the winter months. Asymmetry resulting from differences in aspect is statistically insignificant both in east-trending valleys without defined stream channels and in south-trending valleys with meandering streams. The absolute maximum angle is found to be an excellent indicator both of local changes in slope form and of the nature of the profiles as a whole. The degree of organisation of all profiles studied, in relation to the maximum angle, is high, with the exception of the south-facing slopes in those east-trending valleys in Wyoming which lack defined channels. In general, the maximum angle appears more directly related to the other geometric features of the profile than to the characteristics of soil, vegetation or nearby stream channel. A consideration of all available data on multiply-controlled asymmetry in non-periglacial areas leads to the conclusion that differences in steepness of slopes with northern and southern aspects are more likely to develop in regions of comparatively low humidity and that the valley-wide asymmetry found in Manitoba is the most common form. The strictly localised asymmetry developed in the Wyoming valleys appears to be a specialized phenomenon confined to a narrow area of semi-arid climate. It is suggested that the local conditions of moisture availability are the prime controls of multiply-controlled valley asymmetry, in that they will determine the relative importance of slope and channel processes and hence the nature of the valley-side development. / Arts, Faculty of / Geography, Department of / Graduate

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University libraries exist to support the strategic objectives of their parent universities by providing access to quality and relevant scholarly and scientific information in support of the curricula and research programmes. In fulfilling their core functions, university libraries are increasingly adopting an array of web technologies to deliver quality services to their user community. The aim of this study was to investigate the incorporation of web technologies into the services of university libraries in the Southern African Development Community (SADC) region in order to develop a user-centred model for the deployment of web technologies in university libraries. To achieve this aim, the study was underpinned by the Unified Theory of Acceptance and Use of Technology (UTAUT). The proliferation of information in the electronic environment, along with increased user preference to access digital information, has made the incorporation of web technologies in university libraries a necessity, not an option. These transformative developments are accompanied by increased user demands for user-centred services. These advances justify the significance of this study, as well as the user-centred model developed for the incorporation of web technologies in university libraries which constitutes the original contribution of the research to scientific knowledge. This study falls within a pragmatic paradigm and followed a mixed method research approach, combining both quantitative and qualitative research strategies in data collection and analysis. The population of this study comprised university libraries in the SADC member states whose language of communication is English. Since this population was fairly small in size, quantitative data were collected from the entire population using a questionnaire. Microsoft Excel 2016 was used to analyse the quantitative data. Qualitative data were also collected from librarians via interviews with purposive sampling being used to select the participants. Another set of the population involved undergraduate and postgraduate students from selected universities from whom qualitative data were collected by means of focus group discussions. Purposive sampling was used to select participants in the focus group discussions. Qualitative data were analysed following the thematic qualitative analytical approach. The findings of this study showed that the majority of university libraries in the SADC region have incorporated numerous web technologies for information discovery, for information sharing and promoting library services, for interactive library services, and for content management. The findings also revealed that the UTAUT constructs, namely, performance expectancy, effort expectancy, social influence, and facilitating conditions have had a major influence on the incorporation of web technologies by university libraries, and on librarians' and students' use of these tools. A few university libraries were found to be ill-equipped with information and communication technology (ICT) infrastructure and equipment to facilitate the use of web technologies. This study further established that the UTAUT constructs and the Library 2.0 construct of user-centredness can inform the development of a user-centred model for the incorporation of web technologies by university libraries. The study revealed that the majority of students consider web technologies to be vital tools, enabling them to access study and research information, and to share and publish information with their fellow students, their lecturers and librarians. The study culminated in the design of a user-centred model for the incorporation of web technologies into university libraries services.

Secure multiparty computation refers to the problem where a number of users wish to securely compute a function on their inputs without revealing any unnecessary information. This dissertation focuses on the fundamental limits of secure summation under different constraints. We first focus on the minimal model of secure computation, in which two users each hold an input and wish to securely compute a function of their inputs at the server. We propose a novel scheme base on the algebraic structure of finite field and modulo ring of integers. Then we extend the minimal model of secure computation, in which K users wish to securely compute the sum of their inputs at the server. We prove a folklore result on the limits of communication cost and randomness cost. Then we characterized the optimal communication cost with user dropouts constraint, when some users may lose connection to the server and the server wishes to compute the sum of remaining inputs. Next, we characterize the optimal communication and randomness cost for symmetric groupwise keys and find the feasibility condition for arbitrary groupwise keys. Last, we study the secure summation with user selection, such that the server may select any subset of users to compute the sum of their inputs. This leads us to the MDS variable generation problem. We characterize the optimal individual key rate and the result is interestingly the harmonic number.

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This thesis considers the early copper and copper-alloy metallurgy of the entire Circum-Alpine region. It introduces a new approach to the interpretation of chemical composition data sets, which has been applied to a comprehensive regional database for the first time. An extensive use of GIS has been applied to investigate the role of topography in the distribution of metal and to undertake spatial and geostastical analysis that may highlight patterns of distribution of some specific key compositional element. The Circum-Alpine Chalcolithic and Early Bronze Age show some distinctively different patterns of metal use, which can be interpreted through changes in mining and social choices. But there are also some signs of continuity, in particular those which respect the use of major landscape features such as watersheds and river systems. Interestingly, the Alpine range does not act as a north-south barrier, as major differences in composition tend to appear on an east-west axis. Conversely, the river system seems to have a key role in the movement of metal. Geostastical analyses demonstrate the presence of a remelting process, applicable also in the case of ingots; evidence that opens new and interesting questions about the role of ingots and hoards in the distribution of metal at the beginning of the Metal Age. New tools and new analysis may also be useful to identify zones where there was a primary metal production and zones where metal was mostly received and heavily manipulated.

The master's thesis follows up on the bachelor's thesis called The Folk Song in the Pilsen Region as a Part of the Regional Culture. Primarily, the theoretical part of the thesis aims to compare and contrast two distinct regions, specifically the Pilsen region and the Wallachian region. It focuses on the characteristics of their folk culture including folk architecture, folk costume, folk customs and most importantly folk songs. The thesis deals both with their characteristics typical of Bohemian and Moravian regions in general and their characteristics typical of the Pilsen and the Wallachian regions. The thesis further focuses on folklore festivals, folklore ensembles and folk song collectors associated with these regions. The practical goal of the thesis is the application of Pilsen and Wallachian folk songs in Music classes at upper primary school (or in the corresponding grades of multi-year gymnasium) in the form of a play with folk songs from both regions and arousing pupils' interest in folk songs. The appendix includes pictures and photographs associated with the folklore of the Pilsen and Wallachian regions as well as examples of Wallachian folk songs that can be used as a song-book in Music classes.

Different patterns of uniform-uplift periods associated with passage of the Mendocino triple junction (MTJ) and a change in tectonic regime are based on altudinal spacing analyses of nine flights of marine terraces. Rates of uplift appear to increase from <1 m/ka to 4-5 m/ka, with periods of most rapid uplift that are progressively younger toward the triple junction. The MTJ was about 55 km to the south at about 1 ma ago, where uplift has been uniform at about 1.3 m/ka during the last 300 ka. Maximum uplift of about 4 m/ka is occurring 20-40 km south of the MTJ; prior to about 100-150 ka uplift was slow, being only 0.2-0.5 m/ka. Ten km to the north of the MTJ, accelerated uplift has occurred only during the last 60 ka. Relative strength of soil development in sandy marine deposits on five Pleistocene and Holocene (1.7 to 120 ka) marine terraces near the MTJ is one basis for relative age estimates and correlation of terrace soils. Organic carbon content in the upper 70 cm of the soil profile increases exponentially, and pH decreases exponentially; for both properties steady state is attained by 40 ka. Whole profile content of clay, total free iron oxyhydroxides (Fe(d)), and total free and para-crystalline aluminum oxyhydroxides increase nearly linearly until at least 120 ka. Comparison of these soils with four marine terrace soils (103-405 ka) 100-120 km to the south indicates that maximum percent values of clay and Fe(d) increase exponentially, with highest values reached at about 120 ka. Analysis of three-dimensional morphological properties of 25 coastal drainage basins that have evolved in areas of low (<1 m/ka), intermediate (1-3 m/ka), and high (>3 m/ka) rates of uplift near the MTJ identified channel slopes as the best indicator of tectonism in the landscape. Lower order tributaries reflect tectonically-controlled differences best. The largest streams examined, of third order, are able to adjust to most base-level change and maintain their profile form, whereas lower order streams farther upstream tend to accumulate the effects of net base-level fall, and have steepest profiles in the areas of highest uplift. Although first order streams are excellent indicators of highest uplift rate areas and regional differential tilting, they are less useful in distinguishing between low and intermediate uplift rate areas. Analysis of the longitudinal profile of the main trunk stream of 10 of the 25 drainage basins with the stream-gradient index (Hack, 1957) was useful to broadly categorize uplift rates, and to distinguish between low and intermediate uplift rate streams.