Semi-global techniques in image matching and change detection with applications to civil and environmental engineering.

This work of thesis wants to present a dissertation of the wide range of modern dense matching algorithms, which are spreading in different application and research fields, with a particular attention to the innovative “Semi-Global” matching techniques. The choice of develop a semi-global numerical code was justified by the need of getting insight on the variables and strategies that affect the algorithm performances with the primary objective of maximizing the method accuracy and efficiency, and the results level of completeness. The dissertation will consist in the metrological characterization of the proprietary implementation of the semi-global matching algorithm, evaluating the influence of several matching variables and functions implemented in the process and comparing the accuracy and completeness of different results (digital surface models, disparity maps and 2D displacement fields) obtained using our code and other commercial and open-source matching programs in a wide variety of application fields.

Post-observation feedback as an instigator of teacher learning and change

This paper investigates an on-going study into the nature of the discourse teacher educators (TEds) and student-teachers (Ts) use during postobservation feedback, and explores the feedback discourse in terms of the impact it may have on teacher learning and change. Two types of feedback, confirmatory and corrective, are briefly discussed, and the former is then made the focus of the paper in its role as a potential instigator of teacher learning and change.

White football in South Africa: empire, apartheid and change, 1892-1977

This essay traces the development, domination and decline of white football in South Africa. It suggests that white football was more significant and popular than generally acknowledged and was at the forefront of globalizing football in the early twentieth century. In order to better understand the broader history of twentieth-century South African football, a more detailed examination of the organized white game at the national and international levels is necessary. This historical analysis of elite white football draws from the archives of the Football Association of South Africa. The analysis underscores the important role of white football authorities in the contestation of power and identity in the game in South Africa and abroad. In the first period under consideration (1892-1940s), local football authorities challenged the dominant sports within South Africa. This period was followed in the 1950s by the challenges of professionalism and anti-apartheid organizations. In the final phase (1967-77), officials experimented with football on 'multi-national' and multi-racial lines - a failed reform that led to the demise of white football.

Reform of the New Zealand Health System:problematization, mobilization and change

This paper will seek to explicate the changes in the New Zealand health sector informed by the concepts of problematization, inscription and the construction of networks (Callon, 1986; Latour, 1987, 1993). This will involve applying a framework of interpretation based on the concepts of Latour's sociology of translation. Material on problematization and inscription will be incorporated into the paper in order to provide an explanatory frame of reference which will enable us to make sense of the processes of change in the New Zealand health sector. The sociology of translation will be used to explain the processes which underlie the changes and will be used to capture effects, such as changes in policy and structure, producing new networks within which 'allies' could be enrolled in support of the health reforms.

Inter-organizational co-operation, conflict and change

Relationships between organizations can be characterized by cooperation, conflict, and change. In this dissertation we study cooperation between organizations by investigating how norms in relationships can enhance innovativeness and subsequently impact relationship performance. We do so by incorporating both beneficial aspects of long term relationships as well as “dark side” factors that may decrease innovativeness. This provides a balanced assessment of the factors increasing and decreasing the performance of relationships. Next, we study conflict between organizations by taking a network view on conflict which helps explain why organizations react to conflict. We find stakeholders to have an effect on channel conflict responsiveness. Finally we study change by means of an organization’s ability to successfully add an Internet channel to their distribution system in order to sell its products or services directly to the end-user. We find that an Internet channel is best implemented by organizations that are flexible and we identify several circumstances under which this flexibility is highest.

Flow patterns and performance of distillation trays

It is known that distillation tray efficiency depends on the liquid flow pattern, particularly for large diameter trays. Scale·up failures due to liquid channelling have occurred, and it is known that fitting flow control devices to trays sometirr.es improves tray efficiency. Several theoretical models which explain these observations have been published. Further progress in understanding is at present blocked by lack of experimental measurements of the pattern of liquid concentration over the tray. Flow pattern effects are expected to be significant only on commercial size trays of a large diameter and the lack of data is a result of the costs, risks and difficulty of making these measurements on full scale production columns. This work presents a new experiment which simulates distillation by water cooling. and provides a means of testing commercial size trays in the laboratory. Hot water is fed on to the tray and cooled by air forced through the perforations. The analogy between heat and mass transfer shows that the water temperature at any point is analogous to liquid concentration and the enthalpy of the air is analogous to vapour concentration. The effect of the liquid flow pattern on mass transfer is revealed by the temperature field on the tray. The experiment was implemented and evaluated in a column of 1.2 m. dia. The water temperatures were measured by thennocouples interfaced to an electronic computerised data logging system. The "best surface" through the experimental temperature measurements was obtained by the mathematical technique of B. splines, and presented in tenos of lines of constant temperature. The results revealed that in general liquid channelling is more imponant in the bubbly "mixed" regime than in the spray regime. However, it was observed that severe channelling also occurred for intense spray at incipient flood conditions. This is an unexpected result. A computer program was written to calculate point efficiency as well as tray efficiency, and the results were compared with distillation efficiencies for similar loadings. The theoretical model of Porter and Lockett for predicting distillation was modified to predict water cooling and the theoretical predictions were shown to be similar to the experimental temperature profiles. A comparison of the repeatability of the experiments with an errors analysis revealed that accurate tray efficiency measurements require temperature measurements to better than ± 0.1 °c which is achievable with conventional techniques. This was not achieved in this work, and resulted in considerable scatter in the efficiency results. Nevertheless it is concluded that the new experiment is a valuable tool for investigating the effect of the liquid flow pattern on tray mass transfer.