MSc (Eng), School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand / This study utilises the Life Cycle Environmental Management tool, Life cycle Assessment (LCA) to compare the overall environmental impact of the life cycles of three manufactured emulsions. The emulsions - Aquapel, Hi-phase/composite (liquid/solid rosin) - fulfil a specific function as a sizing agent in the cardboard box industry within the confines of South Africa. As the origins and use of these emulsions are different, the impact assessments of each were evaluated. Using the Simapro Impact 2002+ assessment method, the mid-point impact categories show the most significant impacts in descending order to be Toxicity Impacts on terrestrial ecosystems, Respiratory Inorganics, Climate Change and Non Renewable Energy resources. It would appear that toxicity impacts on terrestrial ecosystems, is the most significant impact. Emission of respiratory inorganics followed by effluent treatment, then electricity used in the emulsion process itself has the next highest contribution in all three processes. The higher contribution to respiratory inorganics by the process using liquid rosin is due to a relatively high contribution from the production of tall oil, a relatively energy intensive process. Climate change is the third most significant contribution. Non renewable energy resources for the Aquapel process shows the highest impact because of its raw material, wax. It is also based on a non-renewable energy resource, crude-oil, whilst the raw material for the Hi-phase/composite process, rosin, is bio-based. When comparing the three emulsion processes according to the Impact 2002+ damage or end point impact categories the relative contributions of the processes shows the relatively close performance of the three processes. The liquid rosin process shows slightly higher potential damages in three out of the four damage categories. The explanation for the differences between the systems follows from the explanations given for the mid-point impact categories. The sensitivity analysis for the Aquapel emulsion process shows negative impacts are produced in descending order for liquid effluent in the ecosystem and human health damage categories. For electricity and paraffin wax negative impacts in the human health and climate change damage categories. The best interventions to reduce life cycle damages is to reduce water and electricity consumption and if possible to find a substitute for paraffin wax. For the Hi-phase/composite liquid / solid rosin emulsion process shows negative impacts are produced in descending order for liquid effluent in the ecosystem and human health / climate change and resources damage categories respectively. The electricity and steam used in both the liquid / solid process produce negative impacts in the human health and climate change damage categories. The best interventions to reduce life cycle damages for the rosin emulsion process are to reduce water, electricity and steam consumption.

Typescript, etc. / Digitized by Kansas Correctional Industries

Natural disasters have always been and probably always will be a problem for humans and their settlements. With global warming seemingly increasing the frequency and strength of the climate related disasters, and more and more people being settled in urban centers, the ability to model and predict damage is more important than ever.The aim of this thesis has been to model and analyze a broad range of disaster types and the kind of impact that they have. By modeling damage indices for disaster types as different as hurricanes and volcanic eruptions, the thesis helps with understanding both similarities and differences between how disasters work and what impact they have on societies experiencing them. The thesis comprises four different chapters in addition to this introduction, where all of them include modeling of one or more types of natural disasters and their impact on real world scenarios such as local budgets, birth rates and economic growth.Chapter 2 is titled “Natural Disaster Damage Indices Based on Remotely Sensed Data: An Application to Indonesia". The objective was to construct damage indices through remotely sensed and freely available data. In short, the methodology exploits that one can use nightlight data as a proxy for economic activity. Then the nightlights data is matched with remote sensing data typically used for natural hazard modeling. The data is then used to construct damage indices at the district level for Indonesia, for different disaster events such as floods, earthquakes, volcanic eruptions and the 2004 Christmas Tsunami. The chapter is forthcoming as a World Bank Policy Research Paper under Skoufias et al. (2017a).Chapter 3 utilizes the indices from Chapter 2 to showcase a potential area of use for them. The title is “The Reallocation of District-Level Spending and Natural Disasters: Evidence from Indonesia" and the focus is on Indonesian district-level budgets. The aim was to use the modeled intensity from Chapter 2 to a real world scenario that could affect policy makers. The results show that there is evidence that some disaster types cause districts to move costs away from more general line items to areas such as health and infrastructure, which are likely to experience added pressure due to disasters. Furthermore, volcanic eruptions and the tsunami led to less investment into more durable assets both for the year of the disaster and the following year. This chapter is also forthcoming as a World Bank Policy Research Paper under Skoufias et al. (2017b).The fourth chapter, titled “Urban Global Impact of Earthquakes from 2004 through 2013", is a short chapter focusing on earthquake damage and economic growth. This chapter is an expansion of the index used in the previous two chapters, where we use global data instead of focusing on a single country. Using a comprehensive remotely sensed dataset of contour mapsof global earthquakes from 2004 through 2013 and utilizing global nightlights as an economic proxy we model economic impact in the year of the quakes and the year after. Overall, it is shown that earthquakes negatively impact local urban light emissions by 0.7 percent.Chapter 5 is named “A Whirlwind Romance: The Effect of Hurricanes on Fertility in Early 20th Century Jamaica" and deviates from the prior chapters in that it is a historical chapter that looks at birth rates in the early 1900s. The goal was to use the complete and long-term birth database for Jamaica and match this with hurricane data to check fertility rates. We create a hurricane destruction index derived from a wind speed model that we combine with data on more than 1 million births across different parishes in Jamaica. Analyzing the birth rate following damaging hurricanes, we find that there is a strong and significant negative effect of hurricane destruction on the number of births. / Natural disasters have always been and probably always will be a problem for humans and their settlements. With global warming seemingly increasing the frequency and strength of the climate related disasters, and more and more people being settled in urban centers, the ability to model and predict damage is more important than ever.The aim of this thesis has been to model and analyze a broad range of disaster types and the kind of impact that they have. By modeling damage indices for disaster types as different as hurricanes and volcanic eruptions, the thesis helps with understanding both similarities and differences between how disasters work and what impact they have on societies experiencing them. The thesis comprises four different chapters in addition to this introduction, where all of them include modeling of one or more types of natural disasters and their impact on real world scenarios such as local budgets, birth rates and economic growth.Chapter 2 is titled “Natural Disaster Damage Indices Based on Remotely Sensed Data: An Application to Indonesia". The objective was to construct damage indices through remotely sensed and freely available data. In short, the methodology exploits that one can use nightlight data as a proxy for economic activity. Then the nightlights data is matched with remote sensing data typically used for natural hazard modeling. The data is then used to construct damage indices at the district level for Indonesia, for different disaster events such as floods, earthquakes, volcanic eruptions and the 2004 Christmas Tsunami. The chapter is forthcoming as a World Bank Policy Research Paper under Skoufias et al. (2017a).Chapter 3 utilizes the indices from Chapter 2 to showcase a potential area of use for them. The title is “The Reallocation of District-Level Spending and Natural Disasters: Evidence from Indonesia" and the focus is on Indonesian district-level budgets. The aim was to use the modeled intensity from Chapter 2 to a real world scenario that could affect policy makers. The results show that there is evidence that some disaster types cause districts to move costs away from more general line items to areas such as health and infrastructure, which are likely to experience added pressure due to disasters. Furthermore, volcanic eruptions and the tsunami led to less investment into more durable assets both for the year of the disaster and the following year. This chapter is also forthcoming as a World Bank Policy Research Paper under Skoufias et al. (2017b).The fourth chapter, titled “Urban Global Impact of Earthquakes from 2004 through 2013", is a short chapter focusing on earthquake damage and economic growth. This chapter is an expansion of the index used in the previous two chapters, where we use global data instead of focusing on a single country. Using a comprehensive remotely sensed dataset of contour mapsof global earthquakes from 2004 through 2013 and utilizing global nightlights as an economic proxy we model economic impact in the year of the quakes and the year after. Overall, it is shown that earthquakes negatively impact local urban light emissions by 0.7 percent.Chapter 5 is named “A Whirlwind Romance: The Effect of Hurricanes on Fertility in Early 20th Century Jamaica" and deviates from the prior chapters in that it is a historical chapter that looks at birth rates in the early 1900s. The goal was to use the complete and long-term birth database for Jamaica and match this with hurricane data to check fertility rates. We create a hurricane destruction index derived from a wind speed model that we combine with data on more than 1 million births across different parishes in Jamaica. Analyzing the birth rate following damaging hurricanes, we find that there is a strong and significant negative effect of hurricane destruction on the number of births.

Dans ce document, nous évaluons l’impact de la microfinance sur des entrepreneurs panaméens, aussi bien sur leur niveau de performance de leurs entreprises que sur leur niveau de vie. Nous allons utiliser une méthode de différence-en-différence et un appariement pour voir l’effet des institutions financières sur les entrepreneurs. La principale contribution de ce mémoire est d’évaluer l’impact des prêts sur les entrepreneurs à travers le temps et pour ce, nous utilisons la différence-en-différence dynamique. D’après nos résultats, la microfinance ne semble pas avoir une influence significative sur les entrepreneurs avec la différence-en-différence. Ce constat est valable aussi bien sur les variables de performances des entrepreneurs que sur les variables de bien-être. Cependant, l’obtention de prêt auprès d’une IMF a un effet sur le revenu avec le modèle d’appariement.

La mise en service d'une infrastructure de transport induit, d'après la théorie économique, une valorisation des territoires à long terme, notamment par le biais de l'immobilier et l'implantation d'activités économiques. Je cherche à déterminer la plus-value générée par une infrastructure de transport en milieu urbain, en liaison avec la recherche de nouveaux financements de ces infrastructures. D'abord, les liens théoriques entre les infrastructures de transport et leurs retombées économiques de long terme sont étudiés. Ensuite, ces effets sont estimés de manière empirique: impacts sur les prix fonciers et immobiliers, sur la construction immobilière résidentielle et sur la création d'activités économiques. Enfin, je tente de fournir une mesure des surplus de fiscalité, réels ou potentiels, pour les territoires, et présente les outils disponibles pour récupérer ces surplus, qui pourraient alors servir pour financer les infrastructures de transport. Le cas étudié est celui du tramway T2, mis en service en 1997 dans le département des Hauts-de-Seine. Les surplus estimés les plus importants sont liés à l'évolution des prix des logements collectifs. Mais ces surplus ne sont pas récupérés par les collectivités locales car les bases de prélèvements fiscaux ne sont pas régulièrement réévaluées. L'existence d'un impact transitoire sur la construction immobilière par des sociétés privées et sur la création d'établissements est également mise en évidence. Ces impacts ont eu des conséquences sur les recettes fiscales des collectivités locales, mais ils sont non mesurables car trop d'éléments non maîtrisables entrent en jeu dans la composition des recettes. / According to economic theory, transport infrastructures have long lasting effects, especially through the real estate and economic activities. The aim is to determine the added value generated by a transport infrastructure in an urban area, in conjunction with the search for ways of funding new transport projects. Firstly, we cover the theoretical links between transport infrastructure and their long term economic benefits. Secondly, we empirically estimate the impacts on land and real estate prices, on residential real estate construction and on the creation of economic activities. Finally, we willl provide an estimation of surplus taxes for the territories, real or potential, and we describe available tools to recover these added values, which could then be used to finance transport infrastructure. The case study is the T2 tramway, opened in 1997 in the Hauts-de-Seine French department. The most important estimated surplus is related to the evolution of collective housing prices. However these added values are not recovered by local authorities because tax bases are not regularly reassessed. We also show the existence of a transitory impact on residential building by private companies and on the creation of firms. These impacts have had an impact on local tax revenues, but we cannot measure it because there are too many non-controllable elements in the composition of revenues. Therefore, the current situation of institutional and fiscal system is not suitable to recover the economic impacts of T2 through taxation.revenues.

acase@tulane.edu / Since 2005, Senegal has scaled up malaria control interventions nationwide, mainly by an approach that allowed reaching people of highest needs. Activities have included vector control interventions such as Insecticide Treated Nets (ITN) and Indoor Residual Spraying (IRS), prevention of malaria in pregnant women, and diagnosis and treatment with an effective anti-malarial. This study aim to evaluate the impact of malaria interventions on all cause mortality among children under five years following the approach of targeting people of highest needs while scaling up of malaria control in Senegal. A “pre/post” study design following the recommendations of the RBM Monitoring and Evaluation Reference Group (MERG) was used. This assessment of the impact of the scalingup of malaria control interventions is based on a plausibility argument. Given that it is difficult to measure mortality resulting from malaria, the objective of the plausibility argument is to demonstrate the association between the scaling-up of malaria interventions and the reduction of all-cause mortality in children under 5 years of age in Senegal. Efforts in vector control led to an increase in the availability of resources, and substantial improvement in intervention coverage. Use of ITN by children under 5 increased from 7 per cent to 35 percent (p<0.001). The greatest increases were observed among populations most at risk of malaria, namely the poorest two quintiles, southern and central regions. Parasite prevalence decreased significantly from 6 per cent in 2008 to 3 per cent in 2010 (p< 0.001). The greatest reductions in anemia and parasitaemia were observed in populations from rural areas, the poorest populations, and populations from the central and southern epidemiological zones, who also displayed the highest increase in ownership and use of ITNs. All-cause under 5 mortality decreased by 40 per cent. Kaplan-Meier survival analysis showed better child survival over the period 2005–2010 compared to 2000–2005. Except for the region of Dakar, child survival estimates were higher in areas with the lowest prevalence of malaria. In addition, All-cause mortality in children under 5 years was significantly lower during the period after the scaling-up of malaria control interventions (OR: 0 63; 95% CI: 0.46–0.86). Other factors that might affect malaria transmission and child mortality were controlled for in the analysis. Despite increased rainfall malaria morbidity decreased, most strikingly among populations in which access to and use of ITNs increased most. While mortality declined in general during the study period, the greatest decreases in both parasitemia and child mortality were observed among the same populations that had the greatest increase in coverage of malaria control interventions. Similarly, the biggest declines in mortality occurred among the age group most likely to die of malaria, suggesting that malaria control interventions contributed substantially to the decrease in malaria morbidity, and consequently, to all-cause under 5 mortality. Based on the LiST model, the scaling-up of ITNs and IPTp from 2004–2010 averted 5,774 deaths in children under 5. The advent of home-based management to deliver malaria care at home, even in difficult to access rural areas, where the largest number of deaths usually occurs, has greatly contributed to expanding malaria case management across Senegal. All-cause mortality in children under 5 was significantly lower in the period after the scale up of malaria control interventions by targeting people of highest needs. The declines in mortality were greater in the populations and regions where coverage of malaria interventions was highest. The associations held even after taking into account other contextual factors. We drawn the conclusion that malaria control activities reduced malaria related morbidity and mortality, thus contributing to significant declines in all-cause child mortality between 2005- 2010 in Senegal. / 1 / Demba Anta Dione

No description available.

Research Doctorate - Doctor of Philosophy (PhD) / The impact of a small particle with a wear surface can lead to very high strain-rates in the material being encountered. Often predictive erosion models are based on material property parameters taken from quasistatic test conditions. However, the material properties of the impacted wear surface can change dramatically with strain and strain-rate, leaving some doubt as to the validity of an erosion model based on quasistatic parameter values. In this study, a new stress-wave monitoring process is developed for the study of material characteristics and erosion phenomena, at strain-rates approaching 10e6s-1. For this study a newly designed piezo-electric transducer was used to monitor the stress-waves produced by small erosive particle impact events. A computational study was also conducted to aid in the transducer design and location distance from the impact source by considering the effects caused by spatial averaging. Spatial averaging affects the recorded stress-wave signal and is caused by the curvature of the stress-wave as the wave passes through the flat piezo-electric sensing element. This study was conducted using a computational and experimental approach. The joint study allowed significant knowledge to be gained for the study of elasto-plastic impact and stress-wave motion. Finite element analysis (FEA) was used to model the experimental system in detail. The stress-waves produced by the experimental process were directly compared to the FEA model. Once the FEA model was validated, detailed information from the impact event at the surface could be obtained from the model, which would otherwise be difficult if not impossible to obtain experimentally. The issues of wave dispersion have been an underlying problem in the correct interpretation of stress-wave phenomena for many years. The impact of the wear surface causes stress-waves with many frequency components, each component propagating through the wear material at distinct wave velocities. Wave dispersion causes the initial stress-wave pulse to be dispersed into many waveforms. In this study the longitudinal stress-wave was the main waveform studied. FEA simulations were conducted for a purely elastic impact and an impact causing significant plastic deformation of the surface. A comparison between these waveforms showed that in the case of impacts causing plastic deformation, the initial part of the stress-wave, measured from the time of arrival to the first peak, corresponded to the elastic stress component of the impact event at the surface. The characterisation of the waveform in regards to elastic and plastic stress components at the surface was significant for validating model parameters of the Johnson-Cook material model. The stress-wave monitoring process was applied in the first instance to erosive particle impacts to AISI 1020 steel at impact velocities up to 104m/s. A specially designed erosion apparatus, fitted with a modified double disc system was used to impact the 10mm thick steel plate. The piezo-electric transducer was firmly clamped to the rear surface, directly behind the point of impact to obtain the stress-wave signals produced by impacts of 0.4mm zirconia spheres. The study showed that the contact interface of the wear material and the piezo-electric transducer could cause a phase change and amplitude reduction of the stress-wave transmitted to the transducer at wave frequencies above 0.9MHz. The results showed that the most likely cause for the phase shift to occur was the restriction of tensile stresses across the contact interface. For wave frequencies below 0.9MHz, no phase shift or amplitude reduction was apparent in the experimental stress-wave recordings. The combined experimental / FEA study was shown to be able to validate the strain-rate parameter of the Johnson-Cook model. The parameters, which could not be validated by the stress-wave monitoring process, were the parameters relating to plastic deformation of the surface, which were the strain-hardening terms of the Johnson-Cook model. These terms were later validated by studying the extent of plastic deformation at the surface, which occurred in the form of impact craters. By comparing the predicted impact crater depths from the FEA model with the experimental results, the strain-hardening parameters of the Johnson-Cook model could be validated. The robustness of the stress-wave monitoring process was proven for the impact study of ultra high molecular weight polyethylene (UHMWPE) and vinyl ester resin (VER). Unlike AISI 1020 steel, little is know about the high strain-rate response of these polymers. Initial estimates of material property parameters were made by applying computational curve fitting techniques to the stress-strain curves of similar polymers, which were from published results obtained from split Hopkinson’s pressure bar method. The impact and stress-wave study showed UHMWPE and VER to be highly sensitive to strain-rate effects. The main effect was a substantial increase in hardness with increasing strain-rate and it was considered that the hydrostatic stress component contributed to the strain hardening of the polymers. The stress-wave monitoring and FEA computational techniques developed in this study were implemented in the development of an improved erosion model. The model form is similar to that of the well-known Ratner-Lancaster model. The Ratner-Lancaster model assumes wear rate to be proportional to the inverse of deformation energy, where deformation energy is approximated as the product of the ultimate stress and ultimate strain. The improved Ratner-Lancaster model uses the Johnson-Cook model to obtain the von-Mises stress as a function of strain. The area integral of the stress-strain curve is used to derive the deformation energy capacity of the material in the deformed zone close to the surface. The model accounts for strain, strain-rate and thermal effects and is therefore more soundly based on material deformation characteristics valid for erosion events than the Ratner-Lancaster model assumptions. The model developed in this work was applied to the erosion study of 1020 steel, UHMWPE and VER, with good correlation being obtained between experimental erosion rates and model predictions.

Impact is a large and complex field. It embraces both structures as simple as a nail, and more complex systems, such as a car collision. A central feature of impact theory is finding the dependence between the velocities before and after impact. The transformation law of the velocities in an impact interaction can be represented in a purely geometric form, and therefore in the simplest cases, in describing the motion of systems with impacts, it is possible to get by with entirely elementary tools. However, in most engineering applications, the mechanical interactions occurring during a collision are complex. Therefore, impact is usually described by highly complicated mathematical models that can easily lead to cumbersome intricacies. Hitherto, the theories that have been developed either involve a fairly heavy amount of calculations or are severely oversimplified, and, therefore, limited in their application. Our purpose is first to describe the dynamics of a planar collision with as simple equations as possible, and secondly to extract information from those equations with the least and simplest computation. We achieve our task by combining a Kane's dynamical analysis, a simplified model of the deformation of the contact area during impact, and a numerical integration of a set of ordinary differential equations. Subsequently, we verify the consistency, accuracy and efficiency of our results by comparison to those from earlier theories. / Graduation date: 1996

Thesis (Ph. D.)--University of Washington, 1983. / Vita. Includes bibliographical references.