Organisations around the world are today looking for new approaches to maintain or develop competitive advantages, reduce costs, free-up capital and improve quality and service. The traditional customer-supplier relation is characterised by the parties focusing on their own cost reduction, creating win-loose scenarios. Companies today are starting to develop their customer-supplier relations towards more relation-focused approaches. The systems approach is a basis for creating win-win relations between the system components. A win-win relation is looked upon in this thesis as the mutual efforts by customer and supplier in finding and reducing the effect of factors that are causing costs and losses for both customer and supplier. The thesis describes a suggested model for estimating win-win potential for supplier and customer in a maintenance contract regarding civil jet engines. The model is defined as consisting of core values, techniques, and tools for estimating win-win potential. The model is applied in supplier and customer scenario. Findings from applying the model indicate that the supplier's maintenance support performance was a parameter affecting loss factors for both supplier and customer. Investigation pointed out the maintenance supplier's organisation, the supplier's maintenance capacity, and the supplier's spare part inventory as the major causes for problems with maintenance support performance. / <p>Godkänd; 2001; 20070313 (ysko)</p>

The global marketplace is highly competitive and organisations who want to survive long-term, have to continuously improve, change and adapt in response to market demands. Improvements in a company's performance should focus on cost cutting, increasing productivity levels, quality and guaranteeing deliveries in order to satisfy customers. Total Productive Maintenance (TPM) is one method, which can be used to achieve these goals. TPM is an approach to equipment management that involves employees from both production and maintenance departments. Its purpose is to eliminate major production losses by introducing a program of continuous and systematic improvements to production equipment. TPM should be developed and expanded to embrace the whole organisation and all employees should be involved in the process as members of improvement teams. This thesis describes the development of TPM and the TPM implementation process. Research is focused on the implementation process of TPM. The author has had the opportunity of both monitoring and steering a company through part of its TPM implementation program and has conducted a longitudinal study. The implementation process takes several years and this thesis focuses on the initial three years of the process. This study demonstrates that driving forces, obstacles and difficulties often are dependent on the organisation, its managers and the individual employees. It also shows that the TPM implementation process has many similarities to the implementation of other improvement concepts. The analysis of these findings forms the basis for recommendations and guidance for organisations, who intend to implement TPM. / <p>Godkänd; 2000; 20070318 (ysko)</p>

Total Quality Management (TQM) is sometimes considered as a management system in continuous change and consisting of values, methodologies and tools, the aim of which is to increase external and internal customer satisfaction with a reduced amount of resources. Whether TQM improves the performance of companies has been discussed for several years. One way to work with TQM and its values, methodologies and tools is to apply for and work with a quality award. Today, there are international, national, regional, branch-wise and in-company quality awards. The purpose of this thesis is to evaluate whether and describe how working with quality awards affects the performance of companies. The thesis consists of an extended summary and three appended papers on this subject, each one with a different aim and methodology. Two of the papers study the benefits from in-company quality awards for the performance of units, and one paper studies the financial performance of quality award recipients compared with competitors and branch indices. The main conclusion of the thesis, which strengthens earlier published results, is that working with quality awards affects financial performance positively if companies successfully implement TQM, which is the case for quality award recipients. Moreover, the results of this thesis have not been able to show strong evidence proving that the performance of units which have worked with in-company quality awards, but have not yet successfully implemented TQM, are affected by this work. However, such units experience that working with in-company quality awards has positive effects on the customers as well as the employees. / Godkänd; 2002; 20070222 (ysko)

Quality of embedded systems is often demonstrated by performed tests and guaranteed by the quality of the tools used to perform them. Test automation is important in agile development and test frameworks can be considered mission-critical. Thus, it is important to ensure the quality of tools used for quality assurance.This thesis explores how industries with agile processes can learn from safety-related development with plan-driven processes for increased test framework quality. Safety standards often rely on plan-driven processes, focused on discipline in long term prospects with substantial documentation and extensive upfront plans and designs. Agile approaches instead focus on quick adaptation, where software is evolved, undergoes continuous improvements and is delivered incrementally. A case study was performed as an industry collaboration. A literature study extracted approaches from articles and safety standards. Analysis and processing resulted in candidate solutions, principles and practices iteratively refined for general applicability and the industrial context. Insights on implications and perceived industrial value resulted from a focus group, with qualitative and quantitative data collected through moderated group discussions and complementary activities. Finally, this thesis proposes guidelines intended to be generally applicable, with a suggested augmented agile process of sequential ”mini V-models” inherently controlled by Definition of Dones. A case-specific set of proposed guidelines extends the suggestion while embracing insights from the focus group. Also identified was the importance of perceiving the framework as a tool-chain and not a single tool, where interaction sequences and intermediate results can be identified and utilized for analysis and applicable measures. Future work could refine the proposed guidelines with an industrial dynamic validation, and also extend the literature study and expand the focus group for diverse contexts and industrial perspectives.

There is a need for appropriate tools and techniques to undertake the vast task of sound repair, maintenance and rehabilitation of concrete infrastructure which is deemed to be deteriorating at unacceptable rates. Low economic growth predictions lead to limited budgets and a deferring of maintenance. The use of technology could be used to extend the useful life of concrete structures. Structural Health Monitoring Systems (SHMS) can be used to monitor structural integrity and the information obtained from these systems can be used in detecting overloading (on bridges for instance) and to alert asset managers of any due maintenance. Büyüköztürk (2007) argues that conventional methods of inspecting the condition of bridges are generally subjective and that this does not give a true reflection of the state of the structure. The objective of this study is to determine the economic value of using SHMS on South African bridges as opposed to conventional bridge inspection methods. The detailed study was conducted on railway bridges on the Transnet Freight Rail (TFR) Ermelo - Richards Bay coal route to assess the contribution that a commodities line such as this one makes to the South African economy. This study makes use of data from Transnet to establish economic value. It is recommended that the results and recommendations be used for a more detailed study into the value of SHMS to be extrapolated for use on other bridges (e.g. road bridges).

Globally, concrete is the most used construction material. Its embodied energy is relatively low, yet due to the vast quantities that are produced annually, it has substantial greenhouse gas (GHG) emissions associated with it. Of the concrete constituents, the manufacture of clinker - the basis of all conventional cements - contributes the most significant emissions. Therefore, to reduce the emissions associated with concrete manufacture, there has been extensive research into how clinker content can be reduced without compromising desired concrete properties. Existing methods for clinker reduction have, however, only allowed clinker replacement to a limited extent. This research investigated the more efficient use of clinker to minimise clinker content required to achieve desired mechanical and durability properties of concrete. The optimisation of powder (materials < 125 µm) packing, using filler materials with varying fineness, was identified to potentially increase clinker efficiency. The optimisation undertaken was the maximisation of powder packing density but without adversely affecting workability. The investigation entailed the application of analytical particle packing density models as well as experimental investigation. Two particle packing models, the Compaction Interaction Packing Model (CIPM) and the Modified Andreasen and Andersen Curve (MAAC) were applied. Various methods for determining the packing density of powder combinations were investigated which informed the use of the mixing energy test to provide experimental packing density data for the modelling procedures. The CIPM was used to optimise the powder phases of concrete as it incorporated the effect of surface forces on powder packing and the MAAC was used to complete the optimisation of fine and coarse aggregate materials. It was necessary to calibrate the CIPM through the selection of various model constants, based on the minimisation of the average error associated with predicted packing density. Despite the incorporation of surface force effects, the CIPM did not predict the trend in packing density observed for various experimental powder combinations with consistent accuracy. Combinations of cement with limestone of high and low fineness (relative to cement) were most accurately predicted but combinations with limestones of similar fineness to cement were less accurate. It was therefore apparent that the model inadequately accounted for the effects of varying particle size and the corresponding influence of surface forces on these particles. However, for practicality, model constants which minimised overall error were used to determine powder combinations enabling maximum packing density for use in optimised concrete mix design. Concrete mixes were designed in 2 phases. Initially water content was fixed, and limestone content was successively increased to 40 vol. % (Phase 1). Despite the formation of mixtures according to maximum packing density, the results showed that optimisation of packing density with a fixed water content was insufficient to reduce clinker content without adversely affecting compressive strength. However, workability was maintained without excessive superplasticiser (SP) dosage and oxygen permeability, water sorptivity and accelerated drying shrinkage were either improved or not adversely affected. This was attributed to the ability of fine fillers to prevent interconnectivity of the pore structure and the decreased volume of gel hydration products leading to reduced drying shrinkage. Compressive strength was tested for a binary (cement/limestone) and ternary (cement /limestone/fly ash (FA)) binder blend for Phase 2 in conjunction with a substantially reduced water content. Workability was adversely affected and both mixes required high SP doses, however, the FA blend required a relatively lower dose. Compressive strength was again decreased relative to the reference mix but when comparing Phase 1 and 2 mixes with predicted strength for equivalent w/c ratios, compressive strength was relatively unchanged, inferring little benefit of packing optimisation. However, binder efficiency indices (‘bi’) (between 5.3 and 6.9 kg/m3 /MPa) were reduced relative to data from previous investigations with similar strength class (between 10 to 20 kg/m3 /MPa), inferring increased binder performance. Powder packing optimisation thereby has the potential to enable clinker reduction, particularly for lower strength grade concrete, without adversely affecting compressive strength. Furthermore, the relatively unaffected durability indicators portray the beneficial effects of powder packing optimisation on increasing the impenetrability of concrete microstructure and it potential use in applications where durability is of importance. These findings also pointed to further possible reductions in the binder efficiency index below 5 kg/m3 /MPa if water content is further reduced (to maintain low water: cement ratio) and reactive SCMs are incorporated. However, further investigation and understanding of the fundamentals of powder packing is necessary to achieve a fully predictive process of low-clinker concrete mix design that can be universally applicable.

In Namibia, the design and construction specification of concrete (for durability) follows the traditional method of prescribing parameters which over time are believed to produce durable concrete. These parameters include concrete exposure definition, cover, concrete strength, concreting materials and concreting methods. International research has shown that some of these parameters do not have a direct relationship with the durability of “As-built” concrete structures; rather that concrete structures can be designed and constructed to meet specific performance levels of the environment they are built in. In this case, testing of the concrete during design, construction and post-construction (to set acceptable limits and confirm adherence to the limits) becomes part of the process. This project was undertaken to look at how concrete practices (design and construction specification) followed in Namibia have impacted on the durability of concrete structures. To achieve the objective, the approach followed included; first assessing the prevailing concrete conditions (in different areas across Namibia), reviewing current concrete design and construction specifications used in the industry and finally assessing practitioner knowledge on performance-based concrete design and construction specification. Concrete infrastructure in four towns (Walvis Bay, Swakopmund, Arandis and Usakos) were inspected and deteriorations recorded. From these inspections, an evaluation of the causes of the deterioration was undertaken. A comparison was undertaken on the prevalence of different deterioration mechanisms in the four areas. Design standards, for durability, followed by structural engineers in Namibia were reviewed including specifications demanded by different infrastructure developing agencies. The limitations of these were highlighted. Interviews and observations were undertaken with structural engineering practitioners on knowledge of design for concrete durability. From the information collected, the comparison and assessment it was concluded that there is a need to revise the concrete design and construction specification to ensure concrete performs better against the most significant risk to concrete service life; damage due to reinforcement corrosion. Concrete specifications need to have measurable durability parameters which can be used for acceptance of concrete works besides compressive strength. The Namibia Port Authority (NAMPORT) has taken a step in this direction with the development of concrete construction specifications which have adopted the South African Durability Index method as part of the concrete acceptance criteria. Challenges encountered (by NAMPORT) include lack of testing equipment and a lack of knowledge by material testing engineers. With Namibia having the challenge of not having a national concrete construction standard, it is further recommended that major infrastructure developers (Namibia Water Authority, NAMWATER, and Roads Authority, RA) should lead in adoption of similar specifications to the NAMPORT ones. As most engineers in Namibia undertake works for either NAMWATER or RA, the industry will be more willing to undertake the training of engineers on the South African durability index method as it will make economic sense. The training is recommended to include training of laboratories offering material testing services in Namibia.

In manufacturing industry there is a high demand for on line quality control to minimize the risk of incorrectly produced objects. Conventional contact measurement methods are usually slow and invasive, meaning that they cannot be used for soft materials and for complex shapes without influencing thecontrolled parts. In contrast, interferometry and digital holography in combination with computers become faster, more reliable and highly accurate as an alternative non-contact technique for industrial shape evaluation. In digital holography, access to the complex wave field and the possibility tonumerically reconstruct holograms in different planes introduce a new degree of flexibility to optical metrology. With digital holography high resolution and precise three dimensional (3D) images of the manufactured parts can be generated. This technique can also be used to capture data in a single exposure,which is important when doing measurements in a disturbed environment.The aim of this thesis is to perform online process control of free-form manufactured objects by measuring the shape and compare it to the CAD-model. To do this, a new technique to measure surface gradients and shape based on single-shot dual wavelength digital holography and image correlation of speckle displacements is demonstrated. Based on an analytical relation between phase gradients and speckle displacements it is shown that an object is retrieved uniquely to shape and position without the unwrapping problems that usually appear in dual wavelength holography. The method is firstdemonstrated using continues wave laser light from two temperature controlled laser diodes operating at 640 nm. Further a specially designed dual core diode pumped fiber laser that produces pulsed light with wavelengths close to 1030 nm is used. One significant problem when using the dual wavelength single-shot approach is that phase ambiguities are built in to the system that needs to be corrected. An automatic calibration scheme is therefore required. The intrinsic flexibility of digital holography gives a possibility to compensate these aberrations and to remove errors, fully numerically without mechanical movements. In this thesis I present a calibration method which allows single-shot online shape evaluation in a disturbed environment. It is shown that phase maps and speckle displacements can be recovered free of chromatic aberrations. This is the first time that a single-shot dual wavelength calibration is reported by defining a criteria to make an automatic procedure.By the results of the presented work, it is experimentally verified that the single-shot dual wavelength digital holography and numerically generated speckle images can be used together with digital speckle correlation to retrieve and evaluate the object shape. The proposed method is also robust to large phasegradients and large movements within the intensity patterns. The advantage of the approach is that, using speckle displacements, the shape measurement can be done even though the synthetic wavelength is out of the dynamic range of the height variation of the object.

Concrete deteriorates due to, but not limited to the ingress of deleterious substances which react with the cement matrix, reinforcing bars corrosion, mechanical effects, physical effects, structural damages, poor construction practices. All these factors individually or combined, ultimately reduce the expected service lives of the concrete structures. The trends vary with different exposure conditions and geographical locations, and a reference guide is required in South African context. A total of twenty-four concrete structures were visually assessed by different University of Cape Town (UCT) scholars and findings were captured in project reports. The reports of these assessments were analysed in this research to identify the main causes of concrete deterioration and severity of damages in the three provinces considered in South Africa, whilst linking these to environmental exposure conditions and geographical location. It is important to elucidate that deterioration mechanisms and trends were drawn from the limited number of visual assessment reports, and the mechanisms assumed might not have been necessarily correct. The rating of the defects was done using the DER-U rating system, a method available for bridges and retaining walls. DER-U rating system was developed for buildings, exploiting the available rating system for bridges as there is no available established rating system for buildings, and the author considered it an important tool for the preliminary evaluation taking note of all limitations. However, reinforcing bars corrosion has been found to be the most prominent deterioration mechanism on structures assessed and severity was high on the structures located in the Western and Eastern Cape provinces, and was exacerbated by the inadequate cover provided on most structures. Furthermore, it was also noted that the severity of the damage increased with age of a structure. Although petrographic analysis as an additional investigation was required to ascertain Alkali-Silica Reaction (ASR), damage was observed in the Western Cape and Gauteng provinces. Even though the occurrence was low, it still required special attention as the effects are usually disastrous and very expensive to maintain the affected structures. Leaching was observed on all the bridge structures assessed though it was more prominent on the structures situated at the coast. Plastic and drying shrinkage cracks were observed on all structures in the Gauteng province and it has been noted from the literature that shrinkage cracks were exacerbated by very high seasonal temperatures in these provinces. Abrasion was high on all structures on the tidal zones and the elements of structures located in the water courses. The proposed in-situ and laboratory tests have been discussed in this report and they are recommended for full-scale condition assessments to complement the visual assessments in an endeavour to ascertain the mechanisms identified. Evidence of poor maintenance practices was observed in the Eastern Cape province where delamination and spalling were observed on freshly repainted structures. As a result, in South Africa there is undoubtedly, a constant need of developing and employing effective and efficient tools to ensure quality is not compromised. Design engineers must always take into cognisance the exposure conditions and ensure strict quality control measures during the construction phase. Maintenance engineers should take into consideration the location of the structure and deterioration mechanisms in the specific areas when determining the maintenance strategies. The clients should always employ knowledgeable design and maintenance engineers, to ensure durable structures are erected and correctly maintained.

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