Quasi-isotropic (QI) structure for multi-layer fabric panel is believed to be a promising construction to manufacture soft body armour with higher efficiency of ballistic protection based on two hypotheses. The first one is that QI structure panel could involve more secondary yarns in transverse deformation, and the second one is that the more involvement of the secondary yarns could result in the corresponding increase of the energy absorption. However, recent study found that the advantage of QI panel made from Dyneema® woven fabrics was very limited over the aligned panel and potential reasons have not been identified for the lack of systematic studies. Accordingly, this research aims to provide explicit guidance on how to improve the QI structure panels for ballistic protection by studying the mechanisms of aligned and QI panels of multi-layer Dyneema® woven fabrics. The two hypotheses were tested to identify the mechanisms. The ballistic performance of the aligned and QI panels of 2-layer, 3-layer and 4-layer Dyneema® woven fabrics were experimentally investigated using a ballistic test apparatus and a panel clamping system to evaluate the energy absorption of specimens. In order to further study the response of the ballistic panel, a yarn-level Dyneema® woven fabric model was developed. The shear moduli of the yarn (G13 and G23) was found to be the most important elastic constants in simulating ballistic fabrics using orthogonal experiments in this study, and were identified to 0.27GPa and 0.80GPa. The model was agreeably validated by comparing the FE modelling results of multi-layer panels under ballistic impact with the experimental counterparts. Based on this validated model, the areas, shapes of the transverse deformation bases were specifically evaluated. The first hypothesis was verified that the areas of the deformation bases of the back layer fabrics in QI panels of 2-layer, 3-layer, and 4-layer fabric models were more than 10% larger than the areas of the corresponding parts in aligned panel models, especially at medium and late stages. Moreover, the increases of the areas were attributed to the more involvements of the secondary yarns in the deformation, and more circular shapes of the deformation bases of the fabrics in QI panels were identified by using a mathematic measurement method created in this study. The kinetic energy (KE) and total strain energy (IE) evolution of primary yarns and secondary yarns in two panels were further specified. It was found that altering the aligned panel to QI panel not only changed the energy absorption of secondary yarns, also significantly changed that of primary yarns. This indicated that the second hypothesis was not suitable for the cases of panels of the Dyneema® woven fabrics for the influence of the primary yarns after the panel structure changed were neglected. The reason of the alterations of the primary yarns was that the slip-off time or failure time of most primary yarns was changed. The morphology evolution of primary yarns in 2-layer aligned and QI panels were investigated and the results showed that the space between adjacent warp or weft primary yarns and the interactions between some primary yarns and the adjacent primary yarns in another layer significantly affected the slip-off time and failure time of most primary yarns. The influence of these two factors derived from the feature of woven fabrics, which was the crimp. In order to verify the new understanding of the QI ballistic panels from the numerical analysis, a non-crimp fabric, namely Dyneema® SB51, was used to investigate the ballistic performance of the aligned and QI panels. It was found that the energy taken by QI panels was approximately 25% higher than the energy taken by the corresponding aligned panels. This result verifies the analysis conclusion and paves the solid way for further investigation of QI structure panels made up of biaxial fabrics.

Since its beginnings, the aerospace industry has been interested in lowering the weight of aircraft. Moving from performance and economic drivers to environmental design parameters, the weight has continuously been a major focus for this industry. A possible option to reduce weight is to use lighter materials such as fibre reinforced polymer composites (FRPC). This type of material has the potential to be used into cold or moderate high-temperature sections of aero-engines. One major obstacle that hinders composite insertion into aero-engines is the lack of predictive models. In recent years, there has been increasing interest in multiscale modelling as a possible approach to reliably predict composite behaviour. This modelling refers to the simulation of a material’s behaviour through multiple scales, passing on information from one scale to another. The purpose of the present work is to use a commercially available software tool (Altair Multiscale Designer™) to virtually characterize an FRPC made from a non-crimp fabric reinforcement based on its individual constituent properties. The studied composite was a carbon fibre and epoxy system developed by GKN Aerospace. In order to achieve this, a well-characterized unidirectional (UD) carbon fibre prepreg composite was used to calibrate the software. After calibration and verification, different repetitive unit cells were created to capture the non-crimp fabric (NCF) architecture where the effect of fibre waviness was studied. The calibration step allowed for fairly accurate and acceptable results when testing unidirectional or ±45 laminates with different tested UD prepreg material systems. The higher deviation from experimental values was up to 20% with these laminates’ configurations. When simulating more complex layups, such as quasi-isotropic ones, the simulations resulted in over-predicting up to 40% of the composite strength in comparison to experimental data. The study of NCF composites appeared to be more complicated than anticipated. Their complex architecture exhibits complicated failure modes, which could not be captured by the software tool. Large inaccuracy up to 100% were observed between simulation and experimental values of the laminate strengths. In spite of its limitations, the study of NCF composites allowed for a deeper understanding of the software functionalities and findings on the fibre waviness impact onto the predicted stiffness, while the strength of the laminate did not show dependency with the fibre waviness.

Detta examensarbete behandlar den sufiska poeten Jalal Ud-din Rumis dikter som läromedel inom ämnet religionskunskap. Genom att föra samman de två fenomenen religion och poesi undersöker jag på vilket sätt de förhåller sig till varandra i fråga om kunskap om och förståelse inför livet och världen. Vidare behandlar jag sedan hur dessa kopplingar, mellan poesin och religionen, i så fall skulle kunna användas inom religionsundervisningen. Studien är i huvudsak teoretisk med ett religionsdidaktiskt fokus och kretsar kring tolkningen av två dikter.

O presente estudo aborda a fronteira da manufatura de ultraprecisão (UP) da zircônia tetragonal policristalina estabilizada com 3 mol% de ítria (3Y-TZP), realizado por meio da lapidorretificação Ud. A crescente demanda por produtos de cerâmicas avançadas com: elevado acabamento e integridade superficial; alta exatidão de forma; e menor custo de fabricação, tem fomentado pesquisas em diversas áreas da nanociência e nanotecnologia (N&N), visando sobrepujar as limitações ou agregando as principais vantagens dos tradicionais processos de retificação, lapidação e polimento. Em decorrência das excepcionais propriedades mecânicas, a cerâmica 3Y-TZP tem sido extensivamente aplicada na indústria. A 3Y-TZP, entretanto, pode apresentar a desestabilização da sua fase tetragonal em diferentes situações e condições, por exemplo, tendo início na própria manufatura, durante sua usinagem, podendo comprometer seu desempenho. Dessa forma, a 3Y-TZP pode ser considerada um material chave para avaliar e qualificar os processos abrasivos que visam padrão ouro de qualidade que, portanto, não devem suscitar a transformação martensítica. Em meio à pluralidade de processos, destaca-se a lapidorretificação Ud. A presente pesquisa estudou a manufatura UP de superfícies planas de zircônia TZ-3Y-E lapidorretificadas com rebolos de SiC de liga epóxi, almejando rugosidade nanométrica e integridade superficial sem danos microestruturais. Discos de TZ-3Y-E foram prensados isostaticamente a 200 MPa e sinterizados a 1400°C por 2 horas. Os discos foram caracterizados por meio de ensaios de: microdureza; perfilometria de contato e óptica; MEV-FEG; espectroscopia Raman; DRX; e microscopia confocal de epi-fluorescência. Os projetos mecânico e eletroeletrônico da Lapidorretificadora Fiocchi foram evoluídos na direção da retificação cerâmica UP. Os resultados demostraram que o projeto evolutivo da lapidorretificadora Fiocchi foi bem sucedido. A execução e controle das etapas de processamento cerâmico foram fundamentais para obter corpos cerâmicos densos e homogêneos, compatíveis com o acabamento aspirado. Os parâmetros de usinagem que se destacaram foram: profundidade de dressagem de 0,1 mm; pressão de lapidorretificação de 100 kPa; 100 rpm do rebolo e porta-peça; e emulsão (1:40) aplicada por MQF. A aspiração dos resíduos sobre o rebolo melhorou em 21,6% o acabamento, todavia a associação de abrasão dois (rebolo) e três corpos (abrasivos soltos) reduziu em 57,15% a rugosidade. O macroefeito foi visível nos rebolos de #800, #600 e #300 dressados com Ud = 1. A menor rugosidade, Ra = 60,63 nm, proveio do rebolo #300 dressado com Ud=5. O menor desvio de planeza, 0,308 μm, foi obtido com o rebolo de #800 e Ud = 3. O processo alcançou condições de plasticidade da zircônia que apontam para o predomínio dos mecanismos de remoção de microcorte e pulverização de material, sem ocorrência de microtrinca. Segundo ensaios de DRX e Espectroscopia Raman, a lapidorretificação Ud não provocou transformação martensítica. Todavia, o rebolo de #300 gerou alargamento assimétrico dos picos tetragonais nas proximidades de 2θ = 35° e 39° e a reversão das intensidades dos picos tetragonais a 40° e 41°. A reversão foi atribuída a mudança do domínio ferroelástico e a reorientação de planos cristalográficos em nível de cristalito. Os estudos sugerem que a usinagem introduziu tensão residual de compressão que pode ter estabilizado a fase romboédrica. Não há relato de processo capaz de alcançar acabamento nanométrico similar com mesmo tamanho e tipo de abrasivo. A lapidorretificação Ud pode substituir o engajamento da retificação, lapidação e polimento de cerâmica avançada. / The present study focuses on the border of ultra-precision (UP) manufacturing of 3 mol% yttria tetragonal zirconia polycrystal (3Y-TZP), carried out by Ud-lap grinding. The increasing demand for advanced ceramic products with: high surface finish and integrity; high form accuracy; and lower manufacturing cost, has encourage research in several areas of nanoscience and nanotechnology (N&N), to overcome the limitations or adding the main advantages of traditional grinding, lapping, and polishing processes. 3Y-TZP ceramics has been extensively applied by industry due to its exceptional mechanical properties. The 3Y-TZP, however, can present destabilization of its tetragonal phase in different situations and conditions. In the beginning of its manufacture, during its machining for instance, which may compromise its performance. Thus, the 3Y-TZP can be considered a key material to evaluate and qualify abrasive processes aiming gold standard quality that, therefore, should not raise the martensitic transformation. In the midst of plurality of processes, it is noteworthy the Ud-lap grinding. This research studied the UP manufacture of flat TZ-3Y-E zirconia surfaces lap ground with epoxy binder SiC grinding wheels, aiming to nanometer roughness and microstructural integrity without damage. Discs of TZ-3Y-E were isostatically pressed at 200 MPa and sintered at 1400 °C for 2 hours. The discs were characterized by tests of: microhardness; contact and optical profilometry; FEG-SEM; Raman spectroscopy; XRD; and confocal epi-fluorescence. Mechanical and electric-electronic designs of Fiocchi lap grinder were developed toward the UP ceramic grinding. Results showed that the developmental design of Fiocchi lap grinder was successful. The accomplishment and control of ceramic processing stages were essential for dense and homogenous ceramic bodies, compatible with the finish aspired. The machining parameters that stood out were: 0.1 mm depth of dressing; 100 kPa lap grinding pressure; 100 rpm grinding wheel and workpiece-holder; and emulsion applied by MQF. Suction of debris on the grinding wheel has improved finishing in 21.6%, however the combination of two-body abrasion (grinding wheel) and three-body abrasion (loose abrasives) decreased roughness in 57.15%. The macroeffect was visible on #800, #600, and #300 dressed with Ud = 1. The best finishing, Ra = 60.63 nm, came from #300 grinding wheel dressed with Ud = 5. The smallest flatness deviation, 0.308 μm, was obtained with the #800 grinding wheel and Ud = 3. The process has achieved zirconia plasticity conditions pointing towards predominance of microcutting and pulverization material removal mechanism without causing microcrack. According to XRD and Raman spectroscopy, the Ud-lap grinding caused no martensitic transformation. However, #300 grinding wheel has generated asymmetric broadening of the tetragonal peaks close to 2θ = 35° e 39° and reversal of the intensities of 40° and 41° tetragonal peaks. The reversal was attributed to ferroelastic switching and reorientation of crystallographic planes into crystallite level. Studies suggest that the machining has introduced compressive residual stress that may have stabilized rhombohedral phase. There is no report of an abrasive process capable of achieving similar nanometric finish with same grit size and type of abrasive. The Ud-lap grinding can replace the engagement of grinding, lapping, and polishing of advanced ceramics.

O presente estudo aborda a fronteira da manufatura de ultraprecisão (UP) da zircônia tetragonal policristalina estabilizada com 3 mol% de ítria (3Y-TZP), realizado por meio da lapidorretificação Ud. A crescente demanda por produtos de cerâmicas avançadas com: elevado acabamento e integridade superficial; alta exatidão de forma; e menor custo de fabricação, tem fomentado pesquisas em diversas áreas da nanociência e nanotecnologia (N&N), visando sobrepujar as limitações ou agregando as principais vantagens dos tradicionais processos de retificação, lapidação e polimento. Em decorrência das excepcionais propriedades mecânicas, a cerâmica 3Y-TZP tem sido extensivamente aplicada na indústria. A 3Y-TZP, entretanto, pode apresentar a desestabilização da sua fase tetragonal em diferentes situações e condições, por exemplo, tendo início na própria manufatura, durante sua usinagem, podendo comprometer seu desempenho. Dessa forma, a 3Y-TZP pode ser considerada um material chave para avaliar e qualificar os processos abrasivos que visam padrão ouro de qualidade que, portanto, não devem suscitar a transformação martensítica. Em meio à pluralidade de processos, destaca-se a lapidorretificação Ud. A presente pesquisa estudou a manufatura UP de superfícies planas de zircônia TZ-3Y-E lapidorretificadas com rebolos de SiC de liga epóxi, almejando rugosidade nanométrica e integridade superficial sem danos microestruturais. Discos de TZ-3Y-E foram prensados isostaticamente a 200 MPa e sinterizados a 1400°C por 2 horas. Os discos foram caracterizados por meio de ensaios de: microdureza; perfilometria de contato e óptica; MEV-FEG; espectroscopia Raman; DRX; e microscopia confocal de epi-fluorescência. Os projetos mecânico e eletroeletrônico da Lapidorretificadora Fiocchi foram evoluídos na direção da retificação cerâmica UP. Os resultados demostraram que o projeto evolutivo da lapidorretificadora Fiocchi foi bem sucedido. A execução e controle das etapas de processamento cerâmico foram fundamentais para obter corpos cerâmicos densos e homogêneos, compatíveis com o acabamento aspirado. Os parâmetros de usinagem que se destacaram foram: profundidade de dressagem de 0,1 mm; pressão de lapidorretificação de 100 kPa; 100 rpm do rebolo e porta-peça; e emulsão (1:40) aplicada por MQF. A aspiração dos resíduos sobre o rebolo melhorou em 21,6% o acabamento, todavia a associação de abrasão dois (rebolo) e três corpos (abrasivos soltos) reduziu em 57,15% a rugosidade. O macroefeito foi visível nos rebolos de #800, #600 e #300 dressados com Ud = 1. A menor rugosidade, Ra = 60,63 nm, proveio do rebolo #300 dressado com Ud=5. O menor desvio de planeza, 0,308 μm, foi obtido com o rebolo de #800 e Ud = 3. O processo alcançou condições de plasticidade da zircônia que apontam para o predomínio dos mecanismos de remoção de microcorte e pulverização de material, sem ocorrência de microtrinca. Segundo ensaios de DRX e Espectroscopia Raman, a lapidorretificação Ud não provocou transformação martensítica. Todavia, o rebolo de #300 gerou alargamento assimétrico dos picos tetragonais nas proximidades de 2θ = 35° e 39° e a reversão das intensidades dos picos tetragonais a 40° e 41°. A reversão foi atribuída a mudança do domínio ferroelástico e a reorientação de planos cristalográficos em nível de cristalito. Os estudos sugerem que a usinagem introduziu tensão residual de compressão que pode ter estabilizado a fase romboédrica. Não há relato de processo capaz de alcançar acabamento nanométrico similar com mesmo tamanho e tipo de abrasivo. A lapidorretificação Ud pode substituir o engajamento da retificação, lapidação e polimento de cerâmica avançada. / The present study focuses on the border of ultra-precision (UP) manufacturing of 3 mol% yttria tetragonal zirconia polycrystal (3Y-TZP), carried out by Ud-lap grinding. The increasing demand for advanced ceramic products with: high surface finish and integrity; high form accuracy; and lower manufacturing cost, has encourage research in several areas of nanoscience and nanotechnology (N&N), to overcome the limitations or adding the main advantages of traditional grinding, lapping, and polishing processes. 3Y-TZP ceramics has been extensively applied by industry due to its exceptional mechanical properties. The 3Y-TZP, however, can present destabilization of its tetragonal phase in different situations and conditions. In the beginning of its manufacture, during its machining for instance, which may compromise its performance. Thus, the 3Y-TZP can be considered a key material to evaluate and qualify abrasive processes aiming gold standard quality that, therefore, should not raise the martensitic transformation. In the midst of plurality of processes, it is noteworthy the Ud-lap grinding. This research studied the UP manufacture of flat TZ-3Y-E zirconia surfaces lap ground with epoxy binder SiC grinding wheels, aiming to nanometer roughness and microstructural integrity without damage. Discs of TZ-3Y-E were isostatically pressed at 200 MPa and sintered at 1400 °C for 2 hours. The discs were characterized by tests of: microhardness; contact and optical profilometry; FEG-SEM; Raman spectroscopy; XRD; and confocal epi-fluorescence. Mechanical and electric-electronic designs of Fiocchi lap grinder were developed toward the UP ceramic grinding. Results showed that the developmental design of Fiocchi lap grinder was successful. The accomplishment and control of ceramic processing stages were essential for dense and homogenous ceramic bodies, compatible with the finish aspired. The machining parameters that stood out were: 0.1 mm depth of dressing; 100 kPa lap grinding pressure; 100 rpm grinding wheel and workpiece-holder; and emulsion applied by MQF. Suction of debris on the grinding wheel has improved finishing in 21.6%, however the combination of two-body abrasion (grinding wheel) and three-body abrasion (loose abrasives) decreased roughness in 57.15%. The macroeffect was visible on #800, #600, and #300 dressed with Ud = 1. The best finishing, Ra = 60.63 nm, came from #300 grinding wheel dressed with Ud = 5. The smallest flatness deviation, 0.308 μm, was obtained with the #800 grinding wheel and Ud = 3. The process has achieved zirconia plasticity conditions pointing towards predominance of microcutting and pulverization material removal mechanism without causing microcrack. According to XRD and Raman spectroscopy, the Ud-lap grinding caused no martensitic transformation. However, #300 grinding wheel has generated asymmetric broadening of the tetragonal peaks close to 2θ = 35° e 39° and reversal of the intensities of 40° and 41° tetragonal peaks. The reversal was attributed to ferroelastic switching and reorientation of crystallographic planes into crystallite level. Studies suggest that the machining has introduced compressive residual stress that may have stabilized rhombohedral phase. There is no report of an abrasive process capable of achieving similar nanometric finish with same grit size and type of abrasive. The Ud-lap grinding can replace the engagement of grinding, lapping, and polishing of advanced ceramics.

Dans un composite stratifié, les plis orientés à 0° par rapport à la direction du chargement pilotent souvent la rupture sous chargement de traction. Les fibres procurent l’essentiel de la rigidité et la résistance de ces plis. Dans ces travaux de thèse, le comportement en fatigue des plis à 0° est analysé dans des stratifiés unidirectionnels (UD) et multidirectionnels, au moyen d’essais de fatigue multi-instrumentés. Un protocole expérimental est mis en place pour éviter les ruptures prématurées typiques des essais sur UD. L’évolution en fatigue des ruptures de fibres est identifiée par leur émission acoustique. Les mécanismes de fatigue dominés par la rupture des fibres sont analysés par un modèle aux éléments finis développé à l’échelle des constituants. / Under quasi-static and fatigue tension loads, the failure of a carbon fibre reinforced polymer laminate (CFRP) is usually driven by 0° plies. Carbon fibres give most of the stiffness and strength of these plies. In this work, the fatigue behaviour of 0° plies inside unidirectional (UD) and multidirectional laminates is analysed via multi-instrumented tension-tension fatigue tests. A numerical and experimental study is addressed to perform fatigue tests without the typical premature failures of the UD laminates. The acoustic emissions technique is used to identify the evolution law of fibre breaks. A finite element model is developed at the microscale (fibres and matrix) to analyse the fibre-driven fatigue mechanisms.

Scholarship has tended to focus exclusively on connections of Qawwali, a north Indian devotional practice and musical genre, to religious practice. A focus on the religious degree of the occasion inadequately represents the participant’s active experience and has hindered the discussion of Qawwali in modern practice. Through the examples of Nusrat Fateh Ali Khan’s music and an insightful BBC radio article on gender inequality this thesis explores the fluid musical exchanges of information with other styles of Qawwali performances, and the unchanging nature of an oral tradition that maintains sociopolitical hierarchies and gender relations in Sufi shrine culture. Perceptions of history within shrine culture blend together with social and theological developments, long-standing interactions with society outside of the shrine environment, and an exclusion of the female body in rituals. To better address Qawwali performances and their meanings, I foreground the perspectives of shrine social actors and how their thoughts reflect their community, its music, and gendered spaces. / text

L'un des avantages majeurs des stratifié composites à renforts de fibres longues est la capacité d'orienter les fibres de chaque pli afin d'optimiser ses propriétés mécaniques telles que la résistance et la rigidité, par rapport aux chargements imposés. Malgré d'excellentes propriétés dans le plan, les stratifiés présentent un problème propre aux matériaux réalisés par stratification: la rupture inter-laminaire. Ce mécanisme de rupture se caractérise par un décollement ou une décohésion entre les plis du stratifié. Il est couramment appelé le "délaminage". De plus, peu d'information existe dans la littérature concernant le délaminage en mode II pur. Par ailleurs, cette dernière est encore moins prolifique en ce qui concerne les sollicitations rapides. L'objectif de cette thèse est donc d'étudier ce mode de délaminage lorsque ce type de matériau composite est soumis à des sollicitations rapides. L'essai de délaminage en mode II CLS (Cracked-Lap-Shear) a été appliqué à deux types standards de matériaux composites unidirectionnels en utilisant un système de guidage assurant un mode II quasi-pur. Les campagnes d'essais ont été réalisées à l'aide d'une machine de traction à grande vitesse. Une caméra rapide de type Photron a été utilisée pour filmer la fissuration jusqu'à des vitesses de propagation de l'ordre de 1000m/s. L'application de la technique de mesure de champ par Corrélation d'images a permis de mesurer les champs de déplacement locaux au voisinage de la tête de la fissure. Deux méthodes différentes de mesure sont étudiées et appliquées aux essais pour suivre la propagation de la fissure: la méthode de contraste et une méthode combinant la mesure par Corrélation d'image et la méthode des Eléments finis. Par ailleurs, deux approches: la première dite " locale " et la seconde dite " globale " ont été appliquées pour déterminer l'évolution du taux de restitution d'énergie en fonction de la vitesse de propagation de la fissure. Grâce aux résultats obtenus par ces deux approches, nous avons montré que la loi théorique proposées par YANG est capable de bien représenter l'évolution du taux de restitution d'énergie en fonction de la vitesse de propagation de la fissure lors du délaminage en mode II. La loi d'évolution de Yang a donc été validée.

SANITATION, PUBLIC HEALTH AND THE ENVIRONMENT The approach to sanitation worldwide should be ecologically sustainable, i.e. concerned with protection of the environment. This means that sanitation systems should neither pollute ecosystems nor deplete scarce resources. It further implies that sanitation systems should not lead to degrading water or land and should, where possible, ameliorate existing problems caused by pollution. More research and better designs are needed. Human excreta can be rendered harmless, and toilet designs that do this in harmony with agricultural and social customs hold promise for the future. Problems with conventional sanitation systems have been shown to include inadequate institutional capacity to deal with the sanitation process, a fixation with providing either a full waterborne system or a VIP toilet, the social acceptability of various systems, and the perception that dry, on-site sanitation systems are inherently inferior. The basic purpose of any sanitation system is to contain human excreta (chiefly faeces) and prevent the spread of infectious diseases, while avoiding damage to the environment. An alternative sanitation technology known as urine-diversion (UD) performs these functions with fewer operational and maintenance problems than those associated with conventional VIP toilets, (for example, it is a major and expensive operation to desludge full pits, which is not the case with UD toilets as the vaults can be quickly and easily emptied using hand tools) and also provides a free, easily accessible and valuable agricultural resource for those who wish to use it. This technology represents one aspect of an approach, or philosophy, termed “ecological sanitation” or “ecosan.” Key features of ecosan are prevention of pollution and disease caused by human excreta, treatment of human excreta as a resource rather than as waste, and recovery and recycling of the nutrients. In nature, excreta from humans and animals play an essential role in building healthy soils and providing valuable nutrients for plants. Conventional approaches to sanitation misplace these nutrients, dispose of them and break this cycle. UD systems have been successfully implemented in many countries, including South Africa where more than 60 000 of these toilets have been built since 1997. However, despite much research having been carried out internationally and locally, various questions still remain, particularly on the health aspects of operation, maintenance, and excreta use or disposal. Not enough is known about the dehydrating processes taking place inside the faeces vault, and there is still disagreement on safe retention periods and microbiological stability of the final product. The roles of dryness, pH, temperature and time in pathogen destruction also need to be further clarified. In addition, it is critically important that toilet users are able to operate and maintain their systems easily and safely, particularly while emptying the vaults and recycling or otherwise dealing with the contents. Engineers need to understand and take all these issues into consideration before they can properly design and implement sustainable UD sanitation systems. It is therefore important to develop guidelines for sanitation practitioners that set out best practices for construction and operation of UD toilets. Construction recommendations are important because good construction facilitates easy operation, and also promotes rapid pathogen destruction. Easy operation in turn directly influences the health risks associated with removing faecal material from the vaults. Handling of faecal material is an aspect inherent in the operation of UD ecological sanitation systems, because emptying of the vault is usually done using hand tools. If the faecal material is also used for agricultural purposes then further handling must of necessity take place. As such, there is a health concern, both for the person(s) handling the material and for the wider public who may be consumers of the fertilised crops. It is therefore necessary that these health concerns be quantified, in order that proper regulation may take place. <b<CONCLUSIONS FROM THE LITERATURE REVIEW The primary aim of sanitation is to prevent the transmission of excreta-related diseases. However, with all sanitation systems there is a risk of disease transmission related to the handling or use of the end product. Therefore, even a well functioning system could enhance pathogen survival and lead to an increased risk of disease transmission for those handling the end products or consuming crops fertilised with them. A greater understanding of pathogen die-off in dry sanitation systems is required where handling and/or use of excreta are expected. Pathogen destruction in dry sanitation systems, particularly in the vaults of urine-diversion (UD) toilets, is mainly dependent on storage time, pH, temperature, humidity, moisture content, organic content of the faecal material, and type of bulking agent added. It is of utmost importance to ensure that the material is safe to handle. This implies that the primary treatment in the vault should, as far as possible, ensure the required level of safety. While much research has been carried out internationally into pathogen destruction in the vaults of UD toilets, the same cannot be said of South Africa. There is also a wide range of results and conclusions, with recommended storage times varying from six months to two years. Construction and operational guidelines are required in order to assist practitioners in these and other respects. Sound management practices could play an important role in reducing the health risks involved in emptying the vaults of UD toilets and the disposal or further use of faecal material. From the public health viewpoint, it is necessary to reduce, as far as possible, the risk of handling faecal material. To do this, a better understanding of the factors influencing pathogen die-off in the vaults is required. FOCUS OF THIS THESIS The primary aim of this thesis is to investigate the efficacy of various methods aimed at enhancing pathogen destruction in the vaults of UD toilets, with the aim of (a) establishing the best combination of factors/methods, in particular the vault storage period required, and (b) producing guidelines for the construction, operation and regulation of these systems. The overall purpose of the research is to establish safety criteria for handling of faecal material from UD toilets. FIELD TRIALS: MICROBIOLOGICAL EFFECTS ON FOOD CROPS FERTILISED WITH FAECAL MATERIAL FROM URINE-DIVERSION TOILETS Recycling excreta to soils reduces the need for chemical fertilisers; however, pathogens are recycled to humans if improper agricultural practices are followed. Concerns about using faecal material include higher pathogenic content in developing countries compared to that in developed countries. This material, as well as that from other sanitation alternatives in small-scale systems, demands more personal involvement from the users (including handling), which constitutes a higher human exposure level compared to that from conventional piped systems. Nevertheless, it is considered that where the material can improve agricultural productivity, it can contribute to improving the nutritional status of the population, thus improving public health. Although ecosan technology is spreading all over the world, and with it the recycling of excreta to soils, only a few researchers have addressed the problems associated with the revalorization practice or documented the pathogen die-off. Moreover, little data about the microbial quality of ecosan faecal material from developing countries (where the health risks are the highest) are available. The objective of this research was thus to investigate the potential health risks of using faecal material in agriculture by determining the pathogen uptake on the surfaces of the edible portions of the crops. Faecal material of between one and three months old was extracted from a number of UD toilets in the eThekwini (Durban) municipal area. This was used primarily for the experimental work described in the next section, but for the purposes of this particular experiment it was first left in a heap in the open air for a further four months. Thereafter it was used as a soil amendment in the cultivation of spinach and carrots. Detailed microbiological tests were conducted on this material as well as on the in situ soil before sowing and after harvesting, on the irrigation water, and on the harvested crops. Applying different rates of material to spinach and carrots, two common edible crops, it was found that the bacteria and fungi content were only noticeable for the higher application rates (>35t/ha), while the helminth ova content varied, both in leaves and stems, depending on the quantity of material applied. Helminth ova content was, for both crops, more prevalent in leaves, suggesting that the ova adhere preferentially to plants rather than soil. It was thus illustrated that there is a health implication involved in growing edible crops in soils amended with ecosan biosolids. Even if in this case the spinach and carrots were cooked before consumption, normal handling of the crops during harvesting and preparation could have caused infection if personal hygiene was unsatisfactory. It is therefore important that crop growers and consumers, as well as proponents of biosolids use, are aware of the storage and treatment requirements for ecosan biosolids before these are applied to soils where crops are grown. DETAILED INVESTIGATION INTO VAULT PROCESSES It is hypothesised that the most advantageous approach to pathogen destruction in a UD toilet vault is to maximise the effects of various environmental factors, e.g. high pH, high temperature, low moisture, type of bulking agent and storage time. In order to quantify these effects a field experiment was set up consisting of 12 UD toilet vaults, each with a different combination of faeces and bulking agent (soil, ash, wood shavings, NaOH or straw), ventilation (ventpipe / no ventpipe) and vault lid material (concrete, metal or perspex). Faecal material was obtained from UD toilets in the eThekwini area, as described above. Temperature probes, which were connected to a data logger, were inserted in the heaps and the logger monitored over a period of nearly 10 months. This enabled a number of graphs to be drawn illustrating the effect of the above parameters on heap temperature over the experimental period. During the coldest week in winter the mean heap temperatures averaged 16,8°C, while the minimum and maximum averaged 14,8°C and 18,8°C respectively. During the warmest week in summer mean heap temperatures averaged 27,6°C, while the minimum and maximum averaged 25,6°C and 29,3°C respectively. In addition, samples were taken at various intervals from each vault as well as from the main heap of faecal material that was left exposed to the elements. The samples were subjected to microbiological testing in order to quantify the pathogen die-off over time for each vault as well as for the main heap. In the vaults, total coliform reduced by 3 log10 (99,9%) at between 130 and 250 days, faecal coliform between 100 and 250 days, and faecal streptococci from 125 days and longer. In the main heap, these times varied from 115 days for both total and faecal coliform to 140 days for faecal streptococci. Viable Ascaris ova were reduced to zero between 44 and 174 days in the vaults and by 44 days in the main heap. The conclusions drawn from the xperimentation were the following: <ul> <li>Influence of ventpipe Ventilation of the vault by means of a ventpipe does not result in any meaningful difference in either the vault temperature or rate of pathogen die-off.</li> <li>Influence of vault lid material The lid material, and by inference also the material of the vault walls, has no significant effect on the temperature of the heap or the associated pathogen die-off.</li> <li>Type of bulking agent While the type of bulking agent used does not significantly influence the temperature of the faecal material, it does have an effect on the rate of pathogen die-off. The ordinary soil mix was seen to give the best results, and this was ascribed to the effect of competing microorganisms in the soil itself.</li> <li>Influence of sunshine and rain The main heap of material (faeces/soil mix) that was exposed to the elements performed among the best in terms of pathogen die-off. Apart from the influence of competing microorganisms in the soil on the pathogens as described above, this good performance was also ascribed to the effect of UV radiation and alternate wetting/drying and heating/cooling cycles, which suggests that open-air exposure is likely to provide the best treatment.</li></ul> Comparing the results of this research with other local and international research, it appears that there is a great deal of convergence in the results. It is concluded that vaults of UD toilets should be sized for a storage period of 12 months from last use. RECOMMENDATIONS FOR CONSTRUCTION, OPERATION AND REGULATION OF URINE-DIVERSION TOILETS The standard of UD toilets in South Africa varies greatly. While there are many good examples of the technology, there are also many that have been ill-conceived and are badly built and poorly operated. Project implementers are responsible for the quality of sanitation schemes and should be equipped with the necessary information to oversee the process. The guidelines are aimed at providing implementers with, firstly, the necessary technical information to build good quality UD toilets and, secondly, the basic operation and maintenance tasks that should be conveyed to the toilet owners. Basic regulatory guidelines for the responsible authorities are also given. The guidelines are intended to be a stand-alone document and some repetition of information from earlier chapters is thus unavoidable. The technology of urine diversion is introduced, followed by basic design and construction guidelines, including drawings, for the superstructure and vault of a UD toilet. Both single- and double-vault toilets are discussed. A number of photographs are also provided, illustrating good and bad building practices. Further aspects discussed are requirements for urine pipes and ventilation. Operation and maintenance of UD toilets are subsequently covered. Topics discussed are dehydration, odour, fly control, cleaning of the pedestal, disposal of anal cleansing material, urine collection and disposal, clearing of blockages in urine pipes, and faeces management. The above guidelines are aimed at designers, builders and toilet users. However, organisations responsible for administering public and environmental health, such as Departments of Health, Environmental Affairs, etc, as well as the local and regional authorities that actually implement the sanitation schemes, should become actively involved in regulating the operation of UD toilets, particularly the removal and disposal of faecal material. Some regulatory guidelines are therefore also included to assist these organisations to set uniform (high) standards in their respective jurisdictions. RECOMMENDATIONS FOR FURTHER RESEARCH RELATED TO THIS THESIS It is deemed important that the field trials conducted in the various vaults as described earlier are repeated in other climatic areas, for example a hot and dry area, as it is likely that different results regarding recommended minimum storage periods will be obtained. This should be supplemented by trials involving co-composting of the faeces mix with other organic material, in order to compare the efficacy of this method with the dehydration process. Further, vault lids made of PVC should be tested for enhancing heat gain in the vaults. Finally, long-tem measurements of heap pH should be made in order to ascertain if high pH amendments (wood ash, lime, etc) do in fact maintain their initial pH level. Additional field trials, similar to those described earlier for spinach and carrots, should be undertaken with a view to making recommendations regarding maximum application rates of faecal material. These should consist of food crops where the edible portions are either in or near to the soil, such as beetroot, onion, potatoes, tomatoes, etc. Trials involving urine should also be considered in order to determine the most advantageous application rate for the various crops. Another important topic is recommended for further research on the subject of UD toilets. At present, virtually all the UD toilets built in the country have been for communities on the lower end of the income scale and who previously had no formal sanitation facility at all or, at best, an unimproved pit toilet. Research carried out by CSIR in a number of communities has revealed people’s resistance to handling their faecal material, while in others it has not been a problem. There is often a general viewpoint in a village that “the municipality must take the faeces away.” However, willingness has also been expressed in some villages to pay for a faeces removal service. For instance, this has borne fruit in an area of Kimberley with UD toilets where householders pay a local resident to remove the faecal material on a regular basis. This is done by means of a wheelbarrow, and the material is stockpiled at a nearby approved facility from where it is destined for co-composting with other municipal waste. However, this has not yet been attempted on a large scale in an area with hundreds, or even thousands, of UD toilets. While a theoretical desktop study has been carried out on the feasibility of setting up a large-scale faeces collection concern, such an enterprise does not yet exist in the country. It is suggested that one be set up utilising a horse- or donkey-drawn cart in a village, or group of villages, with sufficient UD toilets available to ensure that a viable business can be conducted. The cooperation of the particular local authority will be required. If successful faeces collection/disposal services could be established in areas with UD toilets it would greatly enhance the social acceptability, and therefore the viability, of this sanitation technology. / Thesis (PhD(Civil Engineering))--University of Pretoria, 2008. / Civil Engineering / unrestricted

Med bakgrund av fallolyckor som ett betydande folkhälsoproblem, med personligt lidande och omfattande samhällskostnader som följd, undersökte studien produktdesigners möjligheter att skapa en tillgänglig och användbar produkt värd att använda, för personer över 65år, som känner rädsla för att falla (FHM, 2021). I en generell kommentar till FN:s mål för hållbar utveckling, uttrycks vikten av tillämpning av Universell Design (UD) i design av alla nya produkter (UN, 2013). Genom den globalt växande och breda målgruppen, blev det därför centralt att parallellt undersöka hur man kan skapa en bredare tillämpning av UD i designbranschen (WHO, 2018). Designprocessen tog stöd av principerna för UD (Story, Mueller &amp; Mace, 1998) i kombination med Emotionell design och Normans (2004) tre nivåer av emotion. Studien tog även stöd i gerontologisk forskning om fenomenet Fear of falling (FoF), som pekar på att högst nivå av FoF uppmätts hos personer då man ställer rädslan i relation till en aktivitet (Lachman et al., 1998). Studiens empiri genererades huvudsakligen ur metoderna enkätundersökning och dagboksstudie, vilka visade en utbredd strategi bland användarna, att hantera rädsla för att falla genom aktivitetsbegränsning. Aktiviteten att nå högt placerade föremål i hemmet, blev central efter upptäckten att deltagarna i stor utsträckning använder annan utrustning och inredning än en avsedd stegpall. Studiens designbidrag resulterade i en stegpall, vars utformning inte ska motivera att använda en köksstol för aktiviteten. Studiens kunskapsbidrag till designbranschen är ett visuellt greppbart analysresultat, vars styrka är att kommunicera både konkret mätbara och känslomässiga värden i en produkt. / With the background in fall accidents as a significant public health issue, causing both individual suffering and a large social cost, the study examined product designers’ opportunities to create accessible, useful products worth using, for people over 65, who suffers from fear of falling (FHM, 2021). In a general comment to the UN’s sustainable development goal’s, the importance of practising Universal Design (UD) in design of all new products is clearly expressed (UN, 2013). With a globally ageing population and within a broad target group, it became central to explore how to reach a more common practice of UD in the industry of product design (WHO, 2018). The design process was supported by the principles of UD (Story, Mueller &amp; Mace, 1998) combined with Emotional Design and Norman’s (2004) three levels of emotion. The study also included theories from gerontological research on the phenomenon of Fear of falling (FoF), which indicates that a higher level of FoF is expressed by people when it is put in relation to an activity (Lachman et al., 1998). The study’s empirics were mainly generated from the methods Questionnaire and Diary study, which showed a widespread strategy among users, to handle FoF through activity restriction. The activity to reach highly placed objects at home became central after the discovering that the participants often use other equipment and furnishing than a designated step stool. The study’s design proposal resulted in a step stool, which should not justify using a kitchen chair for the activity. The study contributes closing a knowledge gap, which can benefit the design industry with a visually tangible analysis result of both measurable and emotional value in a product.