Energy resources are under tremendous pressure with society’s ever increasing need for electricity. However, resources are becoming scarce and the effect of our power generation on the environment is cause for concern. The cost of electricity is also increasing and thus the need to reduce energy consumption is apparent. Most electrical energy generated is consumed by electric motors. Most of these motors are induction motors because they are reliable, efficient and durable. Though these motors are highly efficient, there is still room for improvement when the strain on electrical energy is taken into account. Constructing motors with better efficiency can result in a reduction in energy consumption and cost savings to the consumer. One method of increasing a motor’s efficiency is to use permanent magnets in the construction of the motor’s core. Permanent magnets eliminate the excitation losses experienced by induction machines, thereby increasing the motor’s efficiency. A retrofit design is considered because of the ease of manufacturing for motor suppliers and the ability to apply the solution to existing operating induction machines. The prototype will lay the foundation for future optimisation strategies. The optimised design should provide improved efficiency with a minimum effect on the motors already operating in industry. The design process followed uses the design principles for inductions machines and for sizing permanent magnets. The design is then verified through the use of finite element method software packages, FEMM and ANSYS Maxwell®, and validated by performance testing. A comparison is drawn between the calculated results and the results determined from the performance analysis. The retrofit design performed as expected during the testing with some discrepancies in final values attributed to the manufacturing process. However, the efficiency is lower than designed and requires the implementation of machine optimisation strategies. / MSc (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

Energy resources are under tremendous pressure with society’s ever increasing need for electricity. However, resources are becoming scarce and the effect of our power generation on the environment is cause for concern. The cost of electricity is also increasing and thus the need to reduce energy consumption is apparent. Most electrical energy generated is consumed by electric motors. Most of these motors are induction motors because they are reliable, efficient and durable. Though these motors are highly efficient, there is still room for improvement when the strain on electrical energy is taken into account. Constructing motors with better efficiency can result in a reduction in energy consumption and cost savings to the consumer. One method of increasing a motor’s efficiency is to use permanent magnets in the construction of the motor’s core. Permanent magnets eliminate the excitation losses experienced by induction machines, thereby increasing the motor’s efficiency. A retrofit design is considered because of the ease of manufacturing for motor suppliers and the ability to apply the solution to existing operating induction machines. The prototype will lay the foundation for future optimisation strategies. The optimised design should provide improved efficiency with a minimum effect on the motors already operating in industry. The design process followed uses the design principles for inductions machines and for sizing permanent magnets. The design is then verified through the use of finite element method software packages, FEMM and ANSYS Maxwell®, and validated by performance testing. A comparison is drawn between the calculated results and the results determined from the performance analysis. The retrofit design performed as expected during the testing with some discrepancies in final values attributed to the manufacturing process. However, the efficiency is lower than designed and requires the implementation of machine optimisation strategies. / MSc (Electrical and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

Retrofits of hydraulic and mechanical deep drawing presses often stop with the exchange of the electrical and the hydraulic parts. But that is only half the job. The use of high definition control electronics, faster CPUs and more dynamic hydraulic actuators, offers the opportunity of redesigning the already existing control concepts of the press. In this paper we present how the performance of the press, i.e. the control quality, can be increased for hydraulic ram and cushion axes. The improvement in control quality is achieved through the use of intelligent closed-loop and open-loopcontrol algorithms. Therefore, creasing and crack formation can be reduced, since enhancements in control quality have direct influence on the quality of the forming process. Results will be shown for hydraulic drawing cushion control, i.e. pressure control, as well as for hydraulic ram control, i.e. position, velocity and parallelism control. We present findings for hydraulic cushion control of a mechanical press type Arisa S-4-1600-470-230-LDE (link-drive press with 10 hydraulic cushions) and for ram- / cushion-control of hydraulic press type Müller-Weingarten ZE2100 (multi-curve press with 8-point cushion).

Reinforced Concrete (RC) bridge piers, RC columns along exterior of buildings or those located in parking garages are designed to support large compressive axial loads but are vulnerable to transverse out-of-plane loadings, such as those arising from impacts or explosions. To address a lack of understanding regarding blast and impact response of RC members and the need for retrofit techniques to address deficiencies in existing structures, a multi-disciplinary team including various institutes of the National Research Council and the University of Ottawa has initiated work towards developing a fibre reinforced polymer composite protection system for RC columns subjected to extreme shocks. This thesis will focus on the impact program of the aforementioned project. An extensive literature review was conducted to gain a better understanding of: impact loading and associated dynamic effects; experimental testing of RC members subjected to impact; experimental testing of axially loaded members; and retrofit methods for the protection of RC under impact loading. Five half-scale RC columns were constructed and tested using a drop-weight impact machine and two additional specimens were tested under static loading. Deflections, strain distributions within the columns, impact loads and reaction loads were measured during the testing of the built RC members. Comparisons of experimental datum were established between members with differing levels of axial load and between a retrofitted and a non-retrofitted member. Single-degree-of-freedom analysis was used to obtain the predicted response of certain columns under impact loading allowing for comparisons with experimental data.

The emphasis for UK dwelling refurbishment to date has centred on reducing heating energy use. However, there has been increasing evidence pointing to the need for a more holistic approach. Many existing dwellings already experience overheating during hot weather periods. Climate change projections predict increases in both the frequency and severity of extreme weather events including heat waves such as the one in August 2003, which is estimated to have claimed the lives of over 35,000 people throughout Europe, including 2,000 in the UK. Demand for housing exceeds the supply of new stock and it is estimated that over 70% of the dwellings that will be in use in 2050 have already been built. Therefore existing dwellings will require adaptation to provide more comfortable and safe environments, to reduce both summertime overheating and heating energy use. In this research, dynamic thermal simulation computer modelling was used to assess and rank the effectiveness of selected single and combined passive interventions (adaptations) on dwelling overheating during a heat wave period. Simulations were also carried out to assess the effect of those interventions on annual space heating energy use. Four distinct dwelling types were selected to represent the housing stock in London and South East England, producing seven modelling variants: 19th century end and mid-terraced houses; 1930s semi-detached house; 1960s ground, mid and top floor flats and a modern detached house. Simulations were carried out for two different occupancy profiles and four building orientations and the cost of interventions was also considered in the analysis. The first occupancy profile assumed a ‘typical’ family who left the dwellings unoccupied during the daytime, the second assumed residents who were at home all the time (e.g. elderly or infirm). Of the dwelling types studied the 1960s mid and top floor flats and the modern (2006) detached house (Tier 2) experienced more than twice as much overheating as the other dwelling types (Tier 1). Tier 2 dwellings were “harder to treat” and unlike Tier 1 dwellings their overheating exposure could not be eliminated using the selected passive interventions. It was possible to substantially reduce overheating and annual heating energy use of Tier 1 dwellings at moderate cost, whereas the costs for retrofitting Tier 2 dwellings were estimated to be many times higher. The results demonstrated that overheating exposure can be significantly greater for residents who have to stay at home during the daytime and they should not, where possible, be housed in the most vulnerable dwellings. External window shutters were found to be the single most effective intervention for overheating reduction in most of the dwelling types considered, typically resulting in a 50% reduction in overheating exposure. The exception was the 19th century terraced houses, where applying a solar reflective (high albedo) coating to the solid external walls was often more effective. In some cases the addition of insulation increased overheating and external wall insulation consistently outperformed internal wall insulation when considering the effect on overheating, though the latter could be effective as an element of combined interventions. Adaptation should therefore be considered together with mitigation, both in design practice and in regulations. If existing dwellings (for example the 19th century terraced houses) are retrofitted for energy efficiency, without considering summer use, overheating could increase dramatically. Subsequent corrective measures could be costly and energy efficiency may suffer as a result. This research builds on previous publications and research to generate systematic, quantitative and holistic guidance for retrofitting UK dwellings to reduce overheating risk during heat waves, whilst minimising annual space heating energy use and considering the cost of retrofit. An interactive retrofit advice toolkit has been developed (and made publicly available) as part of the research, which allows selection of the best performing interventions within a given budget. Recommendations for further development of the research are also suggested.

Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / William P. Winslow III / This project is of a personal interest to me, because Junction City, Kansas has been my home town since birth. The city is a rapidly growing community with a strong military presence from nearby Fort Riley, Kansas. The project will explore the capacity for effective growth while preventing the degradation of fragile natural resources within the community. It will also provide new amenities for the people of Junction City as well as capitalize on the existing natural amenities. The project provides storm water management solutions for an existing retail development and a proposed mixed use development incorporating sustainable practices. Studying the history and progressive nature of Junction City provides an understanding of how to embrace the design within the surrounding landscape. A model for responsible mixed use retail and residential development in Junction City is provided through this project. Storm water best management strategies were also implemented to improve the oxbow wetlands by capturing the first flush storm event as well as a 25 year storm event. Finally, the project should continue to shape the history and enthusiasm of Junction City and its people.

Na construção civil, de uma forma geral, a gestão de projetos pode contribuir positivamente com resultados de um empreendimento. Entretanto, ao longo do desenvolvimento desta pesquisa, constatou-se que a gestão de projetos pode ser ainda mais relevante nos processos de reabilitação de edifícios. Naturalmente, os níveis de complexidade da reabilitação variam conforme o grau de intervenção que se deseja, o que influenciará a formatação do modelo mais adequado de gestão do empreendimento. Mas a organização do empreendimento, sempre que baseada em princípios de gestão de projetos adequados, pode contribuir para a estabilidade no canteiro e para que haja condições que promovam harmonia na relação entre os agentes envolvidos, principalmente entre as equipes de projeto e de obra. O presente trabalho se propõe a aprofundar a discussão sobre essas questões, apresentando os resultados de uma pesquisa bibliográfica sobre o assunto que busca caracterizar os empreendimentos de reabilitação, as interfaces entre projeto e obra, além de discutir o papel da coordenação de projetos no contexto da reabilitação de edifícios. Serão apresentados, ainda, os resultados das pesquisas de campo realizadas em dois empreendimentos de reabilitação: dois em São Paulo, Brasil e, um outro, na cidade de Lyon, na França. / In civil construction the management of design may positively contribute to the results of an enterprise in general way. However, throughout the development of this research, we realize that the management of designs can be much more relevant in building rehabilitation. Of course, the levels of complexity in rehabilitation process vary according to the grade of intervention desired and this affects the formatting of a more adequate model of the enterprise management. Management of designs, whenever it is based on appropriate principles and methods, may contribute to the results at the building site in order to provide a balanced relationship among the agents involved, mainly between the two groups responsible for the designs and its carrying out. This work intends to go deeper into the discussion of these issues by presenting the results of a bibliographical research on the matter, to mark the enterprises in rehabilitation, interfaces between design and work, and to discuss the role coordination of designs plays in the building rehabilitation context. Besides this, it shows the results of field surveys carried out in two rehabilitation enterprises in São Paulo-Brazil and one in Lyon-France.

Reinforced Concrete (RC) bridge piers, RC columns along exterior of buildings or those located in parking garages are designed to support large compressive axial loads but are vulnerable to transverse out-of-plane loadings, such as those arising from impacts or explosions. To address a lack of understanding regarding blast and impact response of RC members and the need for retrofit techniques to address deficiencies in existing structures, a multi-disciplinary team including various institutes of the National Research Council and the University of Ottawa has initiated work towards developing a fibre reinforced polymer composite protection system for RC columns subjected to extreme shocks. This thesis will focus on the impact program of the aforementioned project. An extensive literature review was conducted to gain a better understanding of: impact loading and associated dynamic effects; experimental testing of RC members subjected to impact; experimental testing of axially loaded members; and retrofit methods for the protection of RC under impact loading. Five half-scale RC columns were constructed and tested using a drop-weight impact machine and two additional specimens were tested under static loading. Deflections, strain distributions within the columns, impact loads and reaction loads were measured during the testing of the built RC members. Comparisons of experimental datum were established between members with differing levels of axial load and between a retrofitted and a non-retrofitted member. Single-degree-of-freedom analysis was used to obtain the predicted response of certain columns under impact loading allowing for comparisons with experimental data.

Much of the existing commercial building stock is aging and will be in need of upgrades now or within the next twenty years. Typically, enclosure retrofits consist of adding insulation to the exterior or interior of the existing façade. In this thesis, an alternative solution is examined, whereby a glass façade is added to the exterior of the existing building, forming a double façade. For historic buildings, this could preserve and protect the existing façade without completely covering it up. For outdated buildings, this could modernize the existing façade, giving it the all-glazed appearance that is currently so popular among architects. Regardless of the retrofit motive, it is important to be able to quantitatively compare retrofit solutions to make informed design decisions. As such, building simulation can be an important design tool. At present, there is no available simulation tool that can easily and accurately model a double façade; therefore, a double façade (DoFa) model was developed to fill this gap. A spreadsheet-based, lumped model was created and validated using current complex fenestration models and limited experimental data. Further experimental data is required to validate all aspects of the model. Results showed that the DoFa model can achieve accurate results; however, further development is needed to predict optical properties of venetian blinds and convective coefficients for natural airflow in double façade cavities. The model was used to compare double façades to traditional glazing systems. Results indicated that double façades can perform comparably to double glazing with outdoor shading in summer, and triple glazing in winter. However, the results are only valid for the tested glazing systems. In a second application, the DoFa model was modified to simulate an entire enclosure to compare a double façade retrofit to more traditional retrofit strategies. Results suggested that a double façade provides a good improvement in winter performance, though summer overheating is a concern. For the case study examined, a double façade would have performed better than the chosen retrofit of replacing the windows with double glazing and indoor shading, without insulating the opaque components. The DoFa model can be very useful in creating double façade preliminary design and operation strategies. At present, the DoFa model is an instantaneous, stand-alone tool. Further development is needed to pair the DoFa model with whole building energy simulations.

Recent earthquakes have highlighted the vulnerability of existing structure to seismic loading. Current seismic retrofit strategies generally focus on increasing the strength/stiffness in order to upgrade the seismic performance of a structure or element. A typical drawback of this approach is that the demand on the structural and sub-structural elements can be increased. This is of particular importance when considering the foundation capacity, which may already be insufficient to allow the full capacity of the existing wall to develop (due to early codes being gravity load orientated). In this thesis a counter intuitive but rational seismic retrofit strategy, termed "selective weakening" is introduced and investigated. This is the first stage of an ongoing research project underway at the University of Canterbury which is focusing on developing selective weakening techniques for the seismic retrofit of reinforced concrete structures. In this initial stage the focus is on developing selective weakening for the seismic retrofit of structural walls. This is performed using a series of experimental, analytical and numerical investigations. A procedure for the assessment of existing structural walls is also compiled, based on the suggestions of currently available code provisions. A selective weakening intervention is performed within an overall performance-based retrofit approach with the aim of improving the inelastic behaviour by first reducing the strength/stiffness of specific members within the structural system. This will be performed with the intention of modifying a shear type behaviour towards a flexural type behaviour. As a result the demand on the structural member will be reduced. Once weakening has been implemented the designer can use the wide range of techniques and materials available (e.g. use of FRP, jacketing or shotcrete) to ensure that adequate characteristics are achieved. Whilst performing this it has to be assured that the structure meets specific performance criteria and the principles of capacity design. A target of the retrofit technique is the ability to introduce the characteristics of recently developed high performance seismic resisting systems, consisting of a self centring and dissipative behaviour (commonly referred to as a hybrid system). In this thesis, results of experimental investigations performed on benchmark and selectively weakened walls are discussed. The investigations consisted of quasi-static cyclic uni-directional tests on two benchmark and two retrofitted cantilever walls. The first benchmark wall is detailed as typical of pre-1970's construction practice. An equivalent wall is retrofitted using a selective weakening approach involving a horizontal cut at foundation level to allow for a rocking response. The second benchmark wall represents a more severe scenario where the inelastic behaviour is dominated by shear. A retrofit solution involving vertically segmenting the wall to improve the ductility and retain gravity carrying capacity by inducing a flexural response is implemented. Numerical investigations on a multi-storey wall system are performed using non linear time history analysis on SDOF and MDOF lumped plasticity models, representing an as built and retrofitted prototype structure. Calibration of the hysteretic response to experimental results is carried out (accounting for pinching and strength degradation). The sensitivity of maximum and residual drifts to p-delta and strength degradation is monitored, along with the sensitivity of the peak base shear to higher mode affects. The results of the experimental and analytical investigations confirmed the feasibility and viability of the proposed retrofit technique, towards improving the seismic performance of structural walls.