Many city governments and actors have tested approaches or models and technological developments to address urban service crises. But this has tended to be without much success, as the service delivery gap keeps widening, leading to governance failure. One response to this decline in governance capacity has been the evolution of co-production arrangements. The overarching aim of this thesis was to examine the co-production arrangements of urban sanitation infrastructure provision among multiple actors in informal settlements, and to interrogate whether the predominance of such arrangements was indicative of an alternative form of city governance. Two wards within Arusha city (Tanzania) were selected as case studies. A range of research methods was employed to uncover the landscape of actors involved, and to explore co-productive processes, socio-cultural aspects and other complexities shaping sanitation provision in the two selected informal settlements. Case study methodology was used with a range of data collection methods (household surveys, focus group discussions, document review and semi-structured interviews). The study adopted a relational approach informed by ActorNetwork Theory as the analytical framework for understanding the human-material interactions in the sanitation chain. Key findings indicate that co-production serves a public function, but it is not recognised as such in Tanzanian public policy. Individual and collective co-production arrangements have been established that bring together various state and non-state actors in the sanitation chain to form networks. These networks make service delivery possible, which one actor alone could not deliver. The study reveals that sanitation infrastructure in informal settlements is largely provided by the household, although some are either inactive or captured co-procuders. Further, the narratives indicate that complexities and the contextual factors (including gender-based power dynamics, social norms, values, traditions and culture) shape access to sanitation facilities in the city of Arusha. The study found that the exclusion of women and children from sharing toilet facilities motivated Maasai men to practice defection in open areas. Further, this study speculates on an alternative form of governing city affairs based on actor-networks in the co-production process: co-productive networked governance. Future research is needed to examine how co-productive networked governance could be integrated into the existing city governance structures and how informal governance arrangement could be recognised and enhanced.

3D reconstruction from images, the problem of reconstructing depth from images, is one of the most well-studied problems within computer vision. In part because it is academically interesting, but also because of the significant growth in the use of 3D models. This growth can be attributed to the development of augmented reality, 3D printing and indoor mapping. Progressive stereo reconstruction is the sequential application of stereo reconstructions to reconstruct a scene. To achieve a reliable progressive stereo reconstruction a combination of best practice algorithms needs to be used. The purpose of this research is to determine the combinat ion of best practice algorithms that lead to the most accurate and efficient progressive stereo reconstruction i.e the best practice combination. In order to obtain a similarity reconstruction the in t rinsic parameters of the camera need to be known. If they are not known they are determined by capturing ten images of a checkerboard with a known calibration pattern from different angles and using the moving plane algori thm. Thereafter in order to perform a near real-time reconstruction frames are acquired and reconstructed simultaneously. For the first pair of frames keypoints are detected and matched using a best practice keypoint detection and matching algorithm. The motion of the camera between the frames is then determined by decomposing the essential matrix which is determined from the fundamental matrix, which is determined using a best practice ego-motion estimation algorithm. Finally the keypoints are reconstructed using a best practice reconstruction algorithm. For sequential frames each frame is paired with t he previous frame and keypoints are therefore only detected in the sequential frame. They are detected , matched and reconstructed in the same fashion as the first pair of frames, however to ensure that the reconstructed points are in the same scale as the points reconstructed from the first pair of frames the motion of the camera between t he frames is estimated from 3D-2D correspondences using a best practice algorithm. If the purpose of progressive reconstruction is for visualization the best practice combination algorithm for keypoint detection was found to be Speeded Up Robust Features (SURF) as it results in more reconstructed points than Scale-Invariant Feature Transform (SIFT). SIFT is however more computationally efficient and thus better suited if the number of reconstructed points does not matter, for example if the purpose of progressive reconstruction is for camera tracking. For all purposes the best practice combination algorithm for matching was found to be optical flow as it is the most efficient and for ego-motion estimation the best practice combination algorithm was found to be the 5-point algorithm as it is robust to points located on planes. This research is significant as the effects of the key steps of progressive reconstruction and the choices made at each step on the accuracy and efficiency of the reconstruction as a whole have never been studied. As a result progressive stereo reconstruction can now be performed in near real-time on a mobile device without compromising the accuracy of reconstruction.

Includes bibliography. / Large computer-based information systems seldom achieve unqualified success. The major problem is organisational rather than technical, hence to achieve greater success in system implementation greater emphasis must be given to organisational issues than to technology. Current practise, however, tends to focus on technical issues. The aim of this research was to investigate whether a systems-based approach would lead to better understanding of the system development process, and hence form the basis of a methodology which would lead to greater success in computer-based information system implementation. The thesis comprises four parts. In the first part (Chapters 1 - 5) the literature on systems theory in sociology with particular reference to business organisations is reviewed. This review focuses on the historical development of systems thinking, particularly in business management. Beer's Viable System Model, Checkland' s Soft Systems Methodology, and Hoebeke' s ideas on the adoption of new technology provided the main ideas for developing a conceptual model for the information system development process. In the second part (Chapters 6-9) this model is applied to the information system development process to identify the strengths and weaknesses of current methods. Each stage of system development from planning to implementation is considered from a systems perspective. This involves identifying the key stakeholders, and understanding their role in the development process. In the next part three case studies are examined in the light of the theoretical material. The impact of inter-cultural communication is highlighted in these studies as the developers and customers were from· several different cultures. The author was personally involved as project manager and chief consultant in the development of two of the systems described. He was also fully aware of the progress of the other case because that development was being undertaken in the same office. Regular exchanges of views on the progress of each project took place. In the final chapter the conclusions are presented. The main conclusion is that information system implementation must be undertaken within the overall context of the organisation, must be closely aligned with the organisational business processes, and must address the conflicting needs of the different stakeholders. Effective Communication between system developers and system users is crucial to success. A focussed effort is required to achieve effective communication in a multi-cultural environment.

It is often useful to determine the measures of precision of the directly observed quantities in a triangulation net. Provided the net is not strained these measures are unique to a particular set of observations and weights. Unique measures for the precision of the indirectly observed quantities cannot be found by classical means although several ad hoc approaches can be used to approximate to this measure of the 'inherent strength' of a net. Bjerhammar's theory of generalised matrix inverses can be used to derive measures of precision for the indirectly observed quantities, which may be interpreted as reflecting the inherent strength of the net. The theory of adjustment of a triangulation net by the method of variation of co-ordinates is described, followed by an explanation of the theory bf generalised inverses. Methods for the practical derivation of particular inverses are described, following Mittermayer. The characteristics of Normal, Transnormal and Stochastic Ring inverses in solution of Normal equations BX = R, are described.

The objective of the research was to study the performance of the least squares collocation (LSC) and the fast Fourier transform (FFT) techniques for gravimetric geoid computation. The Land Levelling Datum (LLD) is the South African vertical datum based on more than 100 years old tide gauge measurements of mean sea level (MSL). The LLD is poorly defined so an alternative is required. The SAGEOID10 (Merry, 2009) hybrid geoid model was computed for the purpose of replacing the existing vertical datum. Two gravimetric geoid models were computed using different techniques for evaluation of the Stokes' integral, such as, LSC and one dimensional fast Fourier transform (1D-FFT) technique. The long wavelength component of the geoid models were computed using the EGM2008 geopotential model truncated at degree 720. The use of fast spectral techniques is required due to an increase of both quality and type of data available for geoid determination. The FFT method is most reliable than the LSC method, since it requires less computational time on large data set than the LSC. A system of linear equations of order equal to the number of data points is generated on the LSC method. The geoid model was computed over the province of Gauteng. It was then compared to the SAGEOID10 hybrid geoid model. The computed geoid models, SiPLSC and SiPFFT geoid model compared to the SAGEOID10 model with standard deviation of 5.6cm. The long wavelength component of the computed geoid model compared to the EGM2008 geopotential geoid model with a standard deviation of 4.2cm.

Population increase in African cities have made it hard to reduce their ecological footprint and attain self-sustainability. This made the United Nations to put forward the seventeen sustainable development goals. Three of these goals centre on provision of clean energy and reduction of reliance on fossil fuels. It is therefore important for cities in Africa to chart a path of attaining sustainability. Consequently, the city of Cape Town is leading the drive for a greener city and self-sustainability in energy. Solar energy, which is regarded as a clean and renewable source of energy, makes it possible to generate electricity by using photovoltaics technology. However, the problem of creating awareness as to the potentials of building-integrated solar photovoltaic system persists. The study is aimed at using remote sensing and Geographic Information Systems (GIS) techniques in creating awareness about the potentials of building rooftops for solar photovoltaics installations in an urban setting. In achieving this, Light Detection and Ranging (LiDAR) data and aerial imagery are sourced from City of Cape Town municipality to serve as the primary data input. Four phases of analysis are involved: (1) extraction of whole building roof outline and its roof planes, using the integration of LiDAR-derived products and aerial imagery, in order to determine the surface area of the roof planes. This is achieved by developing a unique two-in-one, object-based classification rulesets; (2) estimating and validating the global solar radiation incidence on each roof plane, using a LiDAR-derived elevation model in a python script utilizing the GRASS script library; (3) evaluating the solar photovoltaic potential of each roof plane, using inputs from two previous phases to create a solar photovoltaic potential database; and (4) deploying the solution online to create awareness, by utilizing JavaScript and Hypertext Mark-up Language (HTML) to implement a map mashup, which incorporates tile map and table services. This results in a web-based solution, which can be queried to retrieve information about the solar photovoltaic potential of a building roof. From the results generated and the system developed, it becomes possible to remotely and sufficiently evaluate buildings in the city for solar photovoltaic potentials, designs and installations. Thereby reducing reliance on the fossil fuel generated electricity and improving the self-sustainability of the city.

Panoramic images (panoramas) are wide-angle images that provide fields of view of up to 360°. They are acquired with a specialised panoramic camera or by stitching a series of images captured with a conventional digital camera. Panoramas have widely been used to texture 3D models generated from laser scanning, for creating virtual reality tour applications, documenting landscape and cultural heritage sites, advertising real estates and recording crime scenes. The goal of this research was to develop an accurate close-range photogrammetric technique for the semi-automatic extraction of 3D information from spherical panoramas. This was achieved by developing a non-parametric method for the removal of distortions from images acquired from fisheye lenses as well as an algorithm, here referred to as the Minimum Ray Distance (MRD), for the fully automated approximate relative orientation of spherical panoramic images. The bundle adjustment algorithm was then applied to refine the orientation parameters of the panoramas; thus enabling accurate 3D point measurement. Finally, epipolar geometry theory was applied to the oriented panoramas to guide the interactive extraction of additional conjugate points. The MRD algorithm has been extended to laser scanning technology for the first approximations of laser scan setup positions and scan orientation prior to a leastsquares based registration. The determination of approximate scanner orientation and position parameters were accomplished using panoramic intensity images derived from full dome laser scans. Thus, a technique for the semi-automatic extraction of 3D measurements from panoramic images has been developed in this research. The technique is most appropriate for applications which do not require dense point clouds and in situations with limited access to funds or as a quick field method to document many features in a short time. This is because a single image orientation is required for several overlapping images as compared to the normal stereo or multi-image photogrammetric approach. It is not suggested that 3D reconstruction from spherical panoramic images should replace traditional close-range photogrammetry or laser scanning; rather, that the user of panoramic images will be offered supplementary information to the conventional and modern cultural heritage documentation approaches.

Bibliography: leaves 91-97. / The quest for sustenance inevitably forces mankind to exploit natural resources found within their environs. In many cases, the exploitation results in massive environmental degradation that disrupts the ecosystem and causes loss of bio-diversity. There is generally a lack of information systems to monitor and provide quantitative information on the state of the affected environment. Decision-makers usually fail to make informed decisions with regard to conservation strategies. The need to provide decision-makers with quantitative environmental information formed the basis of this thesis. An integrated environmental information system (EIS) database was developed according to the Software Development Methodology for three of the identified environmental sectors. This involved detailed user needs assessment to identify the information requirements (both spatial and textual) for each sector. The results were used to design separate data models that were later merged to create an integrated data model for the database application. A fisheries application prototype was developed to implement the proposed database design. The prototype has three major components. The Geographic Information System (GIS) handles the spatial data such as rivers, settlements, roads, and lakes. A relational database management system (RDBMS) was used to store and maintain the non-spatial data such as fisherman ' s personal details and fish catch data. Customized graphical user interfaces were designed to handle the data visualization and restricted access to the GIS and RDBMS environments.

Includes bibliographical references. / Personal privacy issues are relevant to the GIS community. The distribution and dissemination of personal data is greatly facilitated through GIS tools. The use of these tools has been expanded from traditionally geographical operations to applications in geodemographics, and it is particularly in geodemographics where the protection of privacy becomes an issue. This thesis examines existing privacy protection guidelines put forward by international commercial and governmental sectors; the current international position with regards to the protection of privacy is reviewed, and South African legislation pertaining to these issues is explored. On this basis, a set of privacy protection guidelines is developed which can assist GIS managers in South Africa in ensuring that data collection and management do not infringe on personal privacy.

This thesis introduces an alternative formulation for line photogrammetry. The aim was to develop and test a method of computing the position and orientation of a straight line in space using two or more oriented images of that line. The algorithm presented is intended for object reconstruction and is motivated by the need to reconstruct man-made objects in urban areas, such as buildings and the industrial inspection arena. The method aims to obtain a best-fit line through a "pencil of planes". The reconstructed 3D line is defined by two points as opposed to the conventional representation, which uses a point and a direction vector. The approach to this problem involves the calculation of a projection plane for each image containing the perspective centre and two transformed line-point observations in the image. A least squares adjustment involves fitting a straight line as near as possible to the projection planes from all images simultaneously. The adjusted line is referred to as a best-fitting line through a "pencil of planes" (POP). In this project, a mathematical model was formulated for the application of this concept. This algorithm was coded and tested on two cases. A set of scanned aerial images of a residential area with a scale of 1: 5000 provided the primary test case. Lines delineating three roofs visible in the aerial images were reconstructed using the POP method and compared with ground truth data. The lines reconstructed using the POP method were compared to those reconstructed using an existing method of line photogrammetry, proposed by Mulawa (1988). The second test was based on a set of close-range images captured using a small-format digital camera. Lines delineating the bars of a metal frame generally used as a precise control field for camera calibration, were reconstructed. In both test cases, X² tests were applied, and the standard deviations calculated. In the aerial case, standard deviations obtained were generally in the region of about 5cm. The ground resolution of the images was 7.Scm. In the close-range case the ground resolution was approximately 1.3mm, and the standard deviations obtained were generally of the order of 0.7mm. Of the lines computed, 84% of the adjustments passed the X² test. The results obtained confirmed that the POP algorithm is a practicable means of adjusting observations to obtain best-fitting 3D lines using observations made in a set of oriented images.