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Kantor, Radek. "Aplikační případy využití zkapalněného zemního plynu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-401563.
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Pridasawas, Wimolsiri. "Solar-driven refrigeration systems with focus on the ejector cycle." Doctoral thesis, Stockholm : Department of Energy Technology, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4151.
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Lindkvist, Louise. "Exploring Product Life-Cycle Information Flows with a Focus on Remanufacturing." Licentiate thesis, Linköpings universitet, Industriell Produktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-107496.
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Our daily lives and welfare rely heavily on products. Considering that climate change is caused by humans, it is important to handle and use products in a sustainable manner; remanufacturing is one such way to accomplish this. Remanufacturing is an industrial process where products are restored into useful life. However, few products are designed for remanufacturing, which sometimes makes remanufacturing impossible or difficult to perform. Traditionally, the design focus has been on the manufacturing and use phases. The product life-cycle perspective, however, is required to obtain a more sustainable product life-cycle. As the remanufacturing process is characterised by process steps such as inspection, disassembly, cleaning and reprocessing, the often labour-intensive remanufacturing process has specific requirements on the design. Further, the remanufacturing process is characterised by uncertainties such as when used products are expected and what state they will be in when they arrive. Information from the product life-cycle such as drawings and service reports could potentially facilitate the remanufacturing process. Further, feedback from remanufacturing to product design could improve the design of the next generation of products. The objective of this thesis is to identify and analyse product life-cycle information flows with a particular focus on remanufacturing. The design research methodology framework has been used to outline, plan and support the research. Previous research in the area has been assessed through a literature study, while the case study methodology was applied for carrying out the empirical studies. The data collection methods used in the case studies were semi-structured interviews, workshops and document analysis. The result from the literature study shows that feedback such as suggestions for improvement from remanufacturing personnel, process data, and data about wear on components could help to improve the design of the next generation of products. Further, design changes could lead to a more efficient remanufacturing process. The three industrial cases presented in this licentiate thesis fail to explore the full potential of remanufacturing feedback to product design. All in all, remanufacturing is sufficiently included in the information flows of the product life-cycle. Design for remanufacturing is not applied in any of the industrial cases studied.
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Culler, Michael. "Modeling product life cycle networks in SysML with a focus on LCD computer monitors." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34742.
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Electronic waste has become a growing concern in the world among governments, businesses, and consumers. These concerns are well founded as electronics waste presents economic, social, and environmental challenges. Economically, discarding electronic waste into landfills represents inefficient use of valuable materials and energy resources. Socially, improperly recycled electronic waste that takes place in third world countries with poor labor standards represents a moral dilemma for developed countries. Environmentally, electronic waste is a threat to all living organisms as it contains proportionally high levels of poisonous and toxic materials. To deal with these growing challenges a strong response needs to be made by all the stakeholders in the life-cycle of electronic devices.
However, despite the apparent need, compared to the rapid increases in electronic technology that make it faster, more available, and more affordable, the technology to process electronic waste has not kept pace. This fact alone points to the inadequate funding, attention, and research that has been invested in the problem. Though it also points to an opportunity; the opportunity to build an efficient system to deal with the problem using what is already known about the lifecycle of electronic devices. Therefore, the goal of this work is to create a modeling tool to help stakeholders in the lifecycle of electronic devices understand the consequences of their choices as they affect the use of material and energy resources.
To focus the research, LCD computer monitors are chosen as a case study. LCD computer monitors provide a level of sophistication high enough to be interesting in terms of the stakeholders involved, yet simple enough to provide a reasonable scope for this research that is still accessible to the layman
As a corollary to this modeling effort, the relatively new systems modeling language SysML and ParaMagic, a program that integrates analysis modeling capability into SysML, will be evaluated. SysML was designed with Model Based Systems Engineering principles in mind thus it seems that it is a natural fit to the problem domain. Furthermore, testing SysML will provide insight into the advantages and disadvantages of the new language.
The findings with respect to LCD computer monitors show that increasing the number of end of life options and the amount of monitors flowing into those options could result in substantial network wide material and energy savings. The findings with respect to SysML and ParaMagic are mixed. Although SysML provides tremendous modeling freedom, this freedom can result in increased upfront costs for developing executable models. Similarly, ParaMagic was found to be an effective tool for creating small executable models, but as the size of models increase its effectiveness tends to zero.
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Silva, Leon M. (Leon Manuel) 1968. "A partitioning methodology for helicopter avionics system with a focus on life cycle cost." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/82690.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2001.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 111).
by Leon M. Silva.
S.M.
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Kameswari, Rajasekaran Mangalaa. "Silicon biogeochemical cycle along the land to ocean continuum : Focus on Indian monsoonal estuaries." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066713/document.
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Le silicium est le second élément le plus abondant de la croûte terrestre et un nutriment clefs des écosystèmes aquatiques. Il existe de fortes interactions entre Si, le cycle du carbone et les processus biogéochimiques. Cette étude porte sur la variabilité de Si (amorphe-ASi, lithogène-LSi et dissous-DSi) et les isotopes de Si le long du continuum continent-océan. Nous avons étudié la variabilité saisonnière et spatiale de ASi, LSi, DSi et des isotopes dans ~20 estuaires indiens. Nous avons catégorisé les estuaires selon une analyse statistique (PCA et regroupement). Le prélèvement par les diatomées semble être le principal processus contrôlant ASi en saison sèche, surtout au Sud. L’altération et l’érosion contrôlent LSi dans les autres estuaires. En saison humide, l’impact des diatomées n’est pas observé à cause d’une trop forte charge sédimentaire et tous les estuaires sont dominés par les apports lithogéniques. Les compositions isotopiques de Si peuvent tracer les sources de Si et les interactions biogéochimiques. Les résultats isotopiques montrent une différence saisonnière claire avec un impact fort de l’altération aux deux saisons. Les bassins versants du sud-ouest sont très différents des autres bassins du fait de leur topographie et climat. L’impact de l’agriculture et de la couverture forestière est aussi clairement présent dans tous les bassins tandis que la composition isotopique de Si des eaux souterraines résulte d’une combinaison de production et dissolution de minéraux. Ainsi, cette étude montre le rôle prépondérant de l’altération et du type d’argiles formées sur les isotopes de Si, indépendamment des saisons, plutôt que des processus biologiques ou de mélange tels que rapportés précédemmentSilicon is the second most abundant element in Earth’s crust and one of the key nutrient in aquatic ecosystems. There are strong interactions of Si with carbon cycle and biogeochemical processes. The present thesis focused on variability of silicon (amorphous-ASi, lithogenic-LSi and dissolved-DSi) and Si isotopes along the land to ocean continuum. We investigated the seasonal and spatial variability of ASi, LSi & DSi and Si isotopes in ~20 Indian estuaries. We categorize the estuaries using statistical analysis (PCA and cluster analysis). Diatom uptake seems to be the main process controlling ASi during dry period, especially in the South. Weathering and erosion control the variability of LSi in the remaining estuaries. Similarly lithogenic supply controls Si during wet period in all estuaries and no impact of diatoms was seen because of high suspended load. Si isotopic compositions trace the Si sources and biogeochemical pathways. The isotopic results exhibit clear seasonal difference with high impact of type of weathering during both seasons. They show that southwest watersheds are very special in terms of weathering regime compared to the other watersheds because of topography and climate. The impact of agriculture and forest cover on Si cycle is also clearly evidenced in all the basins during wet period. We show that groundwater Si isotopic variability results from a combination of dissolution and production of minerals. Overall, this study shows the preponderant influence of weathering and type of secondary clays on Si isotopes irrespective to the seasons, rather than the biological uptake or mixing as reported elsewhere
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Ibrahim, Josif, and Ahmad Kateesh. "Comparison of two different materials on frame systems with focus on life cycle analysis." Thesis, KTH, Byggteknik och design, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-278747.
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The structural engineer should not only be able to perform design calculations but also findmore efficient solutions for building parts. The purpose of this thesis is to redesign a concreteframe for a house (an apartment building) into a light frame with steel columns andcompartment walls, as well as perform a life cycle analysis for materials on both frames anddetermine the frame with the lowest environmental impact.The result shows that the lightweight frame with steel columns and compartment walls is amuch better choice for the environment as it stands only for 60 000 kg CO2e compared toconcrete frame which stands for 163 000 kg / CO2e. The steel frame emits about 60% lessemissions than the concrete frame.By optimizing steel columns in the upper floors and choosing smaller columns led to ten tonsless mass of steel and less emissions by 15 000 kg / CO2e.The selected compartment wall has a thickness of 309 mm which is 6 mm thicker than theexisting wall which results in a reduction of the area of house by 6 square meters throughoutthe house which can be expensive depending on the location of the house.In conclusion, the material concrete is good when it is needed due to requirements on fire,noise, and durability but also less suitable when not needed. In this case, it is useless with thematerial concrete as the outer wall and can therefore be replaced by a steel columns andcompartment wall instead.Konstruktören ska inte endast kunna utföra beräkningar utan även hitta effektivare lösningar till byggnadsdelar. Syftet med detta examensarbete är att dimensionera om en betongstomme för ett flerbostadshus till en lättstomme med stålpelare och utfackningsväggar samt även utföra en livscykelanalys för material på stommar och bestämma stommen med lägst miljöpåverkan.Resultatet visar att lättstomme med stålpelare och utfackningsvägg är ett mycket bättre val för miljön då står den för 60 000 kg/CO2e jämfört med betongstomme som står för 163 000 kg/CO2e. Stålstommen släpper ut ungefär 60 % mindre utsläpp än betongstommen.Optimering av stålpelare i övre plan och att välja mindre pelare ledde till tio ton mindre massa stål och även mindre utsläpp på 15 000 kg/CO2e.Den valda utfackningsväggen har tjocklek 309 mm vilket är 6 mm tjockare än den befintliga väggen som i sin tur resulterar i en areaförlust med 6 kvadratmeter i hela huset vilket kan vara dyrt beroende på husets läge.Som slutsats är att materialet betong är bra när det behövs på grund av till exempel brand, ljud och beständighet men även mindre lämpligt när det inte behövs. I detta fall är det mindre lämpligt med materialet betong som yttervägg och man kan därför använda utfackningsvägg med stålpelare istället.
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Fischer, Jackie. "Analysis of Two Filamentous Cyanobacteria with a Focus on Life Cycle Progression and Growth Parameters." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1617109026832551.
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Notten, Philippa Josephine. "Life cycle inventory uncertainty in resource-based industries : a focus on coal-based power generation." Doctoral thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/19075.
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The aim of this thesis is to develop an approach to support prospective environmental decision-making in resource-based industries. The specific focus is on coal-based power generation. The objectives of the approach are that it be able to adequately reflect the environmental burdens arising from primary industries, and to make explicit the trade-offs often encountered in environmental decisions. In addition, it needs to take into account that the context in which the assessment takes place affects data availability and quality significantly, and consequently the certainty with which systems can be evaluated. Resource-based processes typically involve large-scale disruption of the local and regional environments, with imprecise processes and diffuse emissions. The modelling of the environmental performance of such processes therefore raises significant challenges, where many disparate sources of data, available at different levels of aggregation, and over various time intervals, have to be brought together into a coherent assessment. An "uncertain" definition of the system is therefore much more meaningful, in which variables are defined over ranges of values to cover inconsistencies and imbalances in the system. The inherently high variability of mining and minerals processes further supports their modelling as ranges of potential performance rather than "typical" operations, where the relevant process of interest must be identified and the variability within the particular process incorporated into the assessment Life cycle assessment (LeA) has received increasing attention for its role in environmental decision making processes, where it supports the process of defining the contribution of human activities to (at least the environmental dimension of) sustainable development. It is therefore the structured approach to environmental decision-making investigated in this thesis to organise the large data sets of varying quality and completeness available around resource-based industries into useful information, able to provide the environmental objective in a decision-making process. LeA is an inherently uncertain procedure in that it combines data sources of varying accuracy and representativeness, and employs subjective judgement in applying this data to future operating systems. Subjective judgements are also present in the definition of the systems, and in the modelling choices determining the accuracy and complexity of the inventory and impact models used. Nonetheless, LeA results are most often presented as single values, which in a comparative analysis, gives the often incorrect impression that one system is always better or worse than another system. A framework has been developed in this thesis to include all relevant sources of uncertainty encountered in LCA models explicitly, where empirical parameter uncertainty, model parameter uncertainty, and uncertainty in model form are investigated in a looped fashion. The innermost loop assesses empirical uncertainty in an iterative probabilistic analysis, using Latin Hypercube sampling of the uncertain input distributions to propagate the data uncertainty to the output, and rank-order correlation analyses to determine the relative uncertainty importance of the parameters input into the model. Model parameter uncertainty is assessed next, by a parametric analysis, or by a combination of sensitivity analyses and a parametric analysis, if a large number of model parameters require consideration. The top-most layer is an assessment of model form, in which alternative model forms are investigated in a sensitivity analysis.
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Bourguet, Nicolas. "Rôle de l'activité hydrolytique bactérienne dans le cycle de la matière organique en milieu marin : focus sur les enzymes lipase." Aix-Marseille 1, 2005. http://www.theses.fr/2005AIX11058.
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Après une étude bibliographique rappelant l'importance de l'activité ectoenzymatique bactérienne dans le cycle du carbone organique en milieu marin, ce manuscrit, ciblé sur l'étude du modèle lipides - lipases, présente les étapes qui ont permis de mettre au point un protocole fournissant des mesures réalistes de l'activité lipase des bactéries marines en suivant la dégradation d'un substrat triglycéride radioactif : la [3H]-trioléine. Au cours d'une étude dans le lagon de Nouvelle-Calédonie, cette nouvelle technique a été comparée avec la technique traditionnelle qui utilise des analogues fluorescents, et s'est révélée être plus spécifique, sensible et reproductible. Puis, comparée aux mesures chimiques de l'hydrolyse d'un triglycéride au cours d'une expérience de biodégradation in vitro, elle s'est avérée refléter de manière significative l'activité lipase s'exerçant in situ. Suite à ces deux étapes de validation, ce protocole a été utilisé au cours d'une étude environnementale en Méditerranée nord-occidentale dans le cadre du projet PROOF-PROPECHE, notamment pour mettre en évidence le rôle joué par l'hydrolyse ectoenzymatique dans l'accumulation de carbone organique dissous au cours de la transition printanière du milieu vers l'oligotrophie
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Pietarila, Kristel M. "A qualitative focus on gender-based physiological differences and cellular signaling needed for modeling /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1421153.
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Miletic, Martin, and Andreas Samuelsson. "Life cycle cost analysis -With focus on the floor types, linoleum and vinyl with or without PUR reinforced surface." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3198.
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The flooring industry is a market that constantly changing every year with new products and improvements. The purpose of this report is to uncover which of the floors, linoleum and vinyl with or without PUR reinforced surface has the lowest life cycle cost for the customer over a 30-year period. The scope of the study is to investigate the three different floors in the public sector in Sweden, Norway, and Finland. A similar study was made many years ago where remarkable result was uncovered. The way used to determining the result in this study is made by two different methods within the LCC. The LCC calculations in this study are based on the primary data collections; qualitative interviews, time study, and observations. Secondary data have also been used in the report. When a customer invests in a floor there are three major costs purchasing, installation, and maintenance. Maintenance will ultimately be the biggest cost because it extends over the entire life cycle while the others are two fixed costs. The analysis uncover that the amount of water and chemical usage to maintain the floors has reduced since the old study. The consumption that has increased is the energy, a result from the increase usage of cleaning machines in the public sector. The most profitable floor to invest in is the vinyl with PUR reinforced surface. This floor has in Sweden and Norway a higher purchasing price than linoleum and vinyl without PUR reinforced surface but in the long run (30 years) its total life cycle cost are lesser than the two others. If the public sector in Sweden invests in a vinyl floor with reinforced PUR surface instead of a vinyl without PUR, the life cycle cost at a hospital or municipality will be reduced by 16,3 percent.
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Larsen, Henrik Fred. "Assessment of chemical emissions in life cycle impact assessment : focus on low substances data availability and ecotoxicity effect indicators /." Department of Manufacturing, Engineering and Management, Technical University of Denmark, 2004. http://tempo.ipl.dtu.dk/ipl/upload/publ/PhD-thesis-rev.pdf.
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Al-Ayish, Nadia. "Environmental Impact of Concrete Structures - with Focus on Durability and Resource Efficiency." Licentiate thesis, KTH, Byggnadsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215037.
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Concrete is essential for the construction industry with characteristic properties that make it irreplaceable in some aspects. However, due to the large volumes consumed and the energy intense cement clinker production it also has a notable climate impact. In order to reach the international and national sustainability goals it is therefore important to reduce the climate impact of concrete structures. There are many ways to influence the environmental impact of concrete and a detailed analysis is one of the actions that could push the industry and the society towards a sustainable development. The purpose of this research is to evaluate the environmental impact of concrete structures and the built environment and to highlight the possibilities to reduce that impact with choice of concrete mix and innovative design solutions. A life cycle assessment (LCA) was carried out to analyze the environmental impact of two thin façade solutions with innovative materials and to evaluate influences of different greenhouse gas reducing measures on concrete bridges. The influence of supplementary cementitious materials (SCM) in terms of climate impact and durability was also analyzed. The results indicate that SCMs have a twofold effect on the climate impact of reinforced concrete structures. Not only do they reduce the greenhouse gases through cement clinker replacement but also by an improvement of durability regarding chloride ingress. Currently, this is not considered in the regulations, which makes it difficult to foresee in LCA at early design stages. The results also show great possibilities to reduce the climate impact through different measures and design alternatives and the need for further development of products and solutions.QC 20171002
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Båge, Renée. "On repeat breeding in dairy heifers : with special focus on follicular dynamics, ovulation, and oocyte quality /." Uppsala : Dept. of Obstetrics and Gynaecology, Swedish Univ. of Agricultural Sciences, 2002. http://epsilon.slu.se/v139.pdf.
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Boije, Henrik. "Generation of Retinal Neurons : Focus on the Proliferation and Differentiation of the Horizontal Cells and their Subtypes." Doctoral thesis, Uppsala universitet, Medicinsk utvecklingsbiologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-150886.
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We have used the chicken retina as a model for investigating cell cycle regulation and cell fate commitment during central nervous system development. This thesis focuses on the characterization of and commitment to the horizontal cell fate in the retina. Horizontal cells are interneurons that provide intraretinal signal processing prior to information relay to the brain. We have identified molecular markers that selectively distinguish the three subtypes of horizontal cells, previously described in the chicken retina based on morphology. Subtype specific birth-dating revealed that horizontal cell subtypes are generated consecutively by biased progenitors that are sensitive to the inhibitory effects of follistatin. Follistatin stimulates proliferation in progenitors by repressing the differentiation signal of activin. Initially, injection of follistatin led to a decrease in committed horizontal cells but as the inhibitory effect dissipated it resulted in an increased number of horizontal cells. During development committed horizontal cell progenitors migrate to the vitreal side of the retina where they become arrested in G2-phase for approximately two days. When the arrest is overcome the horizontal cell progenitors undergo ectopic mitosis followed by migration to their designated layer. The G2-phase arrest is not triggered or maintained by any of the classic G2-arrest pathways such as DNA damage or stress. Nevertheless, we show that the cyclin B1-Cdk1 complex has a central role in maintaining this G2-phase arrest. Two transcription factors, FoxN4 and Ptf1a, are required for the generation of horizontal cells. We show that these factors are also sufficient to promote horizontal cell fate. Overexpression of FoxN4 and Ptf1a resulted in an overproduction of horizontal- and amacrine cells at the expense of ganglion- and photoreceptor cells. We identified Atoh7, a transcription factor required for the generation of ganglion cells, as a Ptf1a transcriptional target for downregulation. Our data support a common horizontal/amacrine lineage separated from the ganglion/photoreceptor lineage by the action of Ptf1a. In conclusion, these data describe several novel characteristics of horizontal cells enhancing our understanding of neural development and cell fate commitment.
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Roy, Axel. "From a complex to a simpler building product Life-Cycle Assessment (LCA) : Focus on simplification of LCA conduct for electronic and electrical equipment." Thesis, KTH, Miljöstrategisk analys, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119851.
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Rizzo, Charlotte. "Wood Waste Derived Fuel: State of the Ard and Development Prospects in France : Focus on Construction and Demolition Wood Wastes." Thesis, KTH, Industriell ekologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-55330.
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Wood wastes are mainly originated from forestry, wood industry and construction and demolition sites activities. Among them, three types of wood waste can be identified: untreated wood waste (raw wood considered as biomass), slightly treated wood wastes (issued from coating or gluing treatments) and highly treated wood wastes (issued from impregnation treatments with CCA and creosote, and considered as hazardous wastes). According to the regulation, management of wastes in Europe is oriented towards more recycling and less elimination. However, among the French requirements, three main trends can be observed in regards of wood waste recovery: only treated wood wastes can be recovered in combustion units, no extensive technologies are allowed to recover highly treated wood wastes, which must then be eliminated by incineration, and slightly treated wood wastes can be either recovered as particle boards or eliminated. However, in this context, the amount of wood wastes from construction and demolition sites reach 7 million of tons in France. Among them, 5% correspond to raw wood, and 25% are slightly treated. The high combustion potential of wood wastes is moreover an opportunity to replace conventional fuel used in combustion units. The four main methods used to treat wood wastes are recycling as particleboards, combustion, incineration and land filling. Due to the various typologies of wood wastes, a conditioning step is needed before recovery. Then, if combustion seems to present advantages because of its neutral carbon impact, life cycle analysis demonstrates that emissions of other pollutants are observed. In addition, it is proved that controlled elimination methods are less impacting than unequipped recovery ones. Recycling is then not always the best practice in regards of the impacts considered in the study. Competition among the different methods treatment and low prices of wood wastes are specific economical aspects that could influence the development of the field. Moreover, the increasing acceptance of people for recovery and local waste treatment methods, as well as the need for energetically independency are factors that can likely promote wood waste derived fuel. These driving forces are evolving in a very rapid way. Regulation is moving towards implementation of standards to promote the development of slightly treated wood waste derived fuel. Technological and social improvement such as sorting at source, and the development of end of pipe treatment methods are also likely to have positive effects. An integrated solution to develop wood waste derived fuel would be to implement strong financial incentives in favour of clean technologies for wood wastes recovery methods. This enhancement could then be the mean to answer the double challenge of wood waste treatment and fossil fuel replacement. Wood wastes are mainly originated from forestry, wood industry and construction and demolition sites activities. Among them, three types of wood waste can be identified: untreated wood waste (raw wood considered as biomass), slightly treated wood wastes (issued from coating or gluing treatments) and highly treated wood wastes (issued from impregnation treatments with CCA and creosote, and considered as hazardous wastes). According to the regulation, management of wastes in Europe is oriented towards more recycling and less elimination. However, among the French requirements, three main trends can be observed in regards of wood waste recovery: only treated wood wastes can be recovered in combustion units, no extensive technologies are allowed to recover highly treated wood wastes, which must then be eliminated by incineration, and slightly treated wood wastes can be either recovered as particle boards or eliminated. However, in this context, the amount of wood wastes from construction and demolition sites reach 7 million of tons in France. Among them, 5% correspond to raw wood, and 25% are slightly treated. The high combustion potential of wood wastes is moreover an opportunity to replace conventional fuel used in combustion units. The four main methods used to treat wood wastes are recycling as particleboards, combustion, incineration and land filling. Due to the various typologies of wood wastes, a conditioning step is needed before recovery. Then, if combustion seems to present advantages because of its neutral carbon impact, life cycle analysis demonstrates that emissions of other pollutants are observed. In addition, it is proved that controlled elimination methods are less impacting than unequipped recovery ones. Recycling is then not always the best practice in regards of the impacts considered in the study. Competition among the different methods treatment and low prices of wood wastes are specific economical aspects that could influence the development of the field. Moreover, the increasing acceptance of people for recovery and local waste treatment methods, as well as the need for energetically independency are factors that can likely promote wood waste derived fuel. These driving forces are evolving in a very rapid way. Regulation is moving towards implementation of standards to promote the development of slightly treated wood waste derived fuel. Technological and social improvement such as sorting at source, and the development of end of pipe treatment methods are also likely to have positive effects. An integrated solution to develop wood waste derived fuel would be to implement strong financial incentives in favour of clean technologies for wood wastes recovery methods. This enhancement could then be the mean to answer the double challenge of wood waste treatment and fossil fuel replacement.Träavfall kommer från skogsbruk, trä‐ och byggbranschen och rivningsplatser. Bland dem kan tre typer av träavfall identifieras: obehandlat träavfall (obehandlat trä betraktas som biomassa), lätt behandlat träavfall (från beläggning eller limning) och högbehandlat träavfall (från impregnering med CCA och kreosot, betraktas som farligt avfall). Enligt avfallsförordningen, är hantering av avfall i Europa inriktad mer mot återvinning och mindre mot eliminering. Bland de franska kraven, kan tre huvudsakliga tendenser iakttas för återvinning av träavfall: endast behandlat avfall kan behandlas i förbränningsanläggningar för energiutvinning, högbehandlat träavfall måste elimineras genom förbränning och lätt behandlat avfall kan antingen återvinnas som spånskivor eller elimineras. I detta sammanhang uppgår mängden träavfall från bygg‐ och rivningsplatser till 7 miljoner ton i Frankrike. Bland dem, motsvarar 5% obehandlat trä, och 25% är lätt behandlat. Den höga förbränningspotentialen för träavfall ger dessutom en möjlighet att ersätta konventionellt bränsle som används i förbränningsanläggningar. De fyra huvudsakliga metoder som används för att behandla träavfall är återvinning i spånskivor, förbränning med energiutvinning, förbränning och deponering. På grund av olika typer av träavfall, krävs ett konditioneringsteg innan återvinning. Även om förbränningen är fördelaktigt på grund av sitt neutrala kol, visar livscykelanalyser utsläpp av andra föroreningar. Dessutom visas att kontrollerade elimineringsmetoder har mindre miljöpåverkar än återvinningsmetoder som ej har rätt utrustning. Återvinning är alltså inte alltid att föredra om man beaktar de effekter som gjorts vid denna undersökningen. Konkurrensen mellan olika behandlingsmetoder och låga priser på träavfall är specifika ekonomiska aspekter som skulle kunna påverka utvecklingen inom området. Dessutom, den ökande acceptansen av människor för återvinning och lokala avfallshanteringsmetoder, liksom behovet av inhemska energikällor är faktorer som sannolikt kan främja bränsle från träavfall. Dessa drivkrafter utvecklas på ett mycket snabbt sätt. Avfallsförordningen är på väg mot införandet av standarder för att främja utvecklingen av lätt behandlat träavfalls bränsle. Tekniska och sociala förbättringar, exempelvis källsortering och utveckling av återvinningsmetoder ger också sannolikt positiva effekter. En integrerad lösning för att utveckla bränsle från träavfall skulle vara att genomföra starka ekonomiska incitament till förmån för ren teknik för återvinning av träavfall. Den här förbättringen kan sedan vara ett medel att anta den dubbla utmaningen av hantering av träavfall och ersättning av fossila bränslen.
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Brewis, Chandre. "Quantifying the environmental dimension of sustainability for the built environment : with a focus on low-cost housing in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20298.
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Thesis (MScEng)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Sustainability is difficult to achieve in a world where population and economic growth leads to increased production of greenhouse gases, resource depletion and waste generation. Today, the environmental dimension of sustainability, which is more commonly known as the natural environment, and the construction industry are two terms often mentioned together. In Europe, 12.4 % of greenhouse gas emissions are induced by the construction and manufacturing industry (Maydl, 2004). Also, 50 % of the resources extracted are used in the construction industry and more than 25 % of waste generated is construction and demolition waste. In South Africa, the building sector accounts for approximately 23 % of the total greenhouse gas emissions (Milford, 2009). Furthermore, 60 % of investment is made in the residential sector where 33 % of the building stock is the focus of the government’s Housing Programme. It is seen that the construction industry significantly impacts the natural environment and the aim should be to reduce this negative impact. Within the local residential sector, the low-cost housing sector presents potential when it comes to sustainable improvements. Each of the three spheres of sustainability, namely economy, natural environment and society, plays a crucial role in this sector. Various studies have been done on the economical and social fields, but little information exists on the impact low-cost houses have on the environment. A need arises to scientifically quantify the environmental impact hereof, therefore it is chosen as the focus of this study. Various methods in order to determine the environmental impact of the built environment exist globally, but they tend to be complex, are used in conjunction with difficult to understand databases and require expensive software. A need for a local quantification method with which to determine the environmental impact of the built environment, more specifically low-cost housing, has been identified. A simple and easy-to-use analysis-orientated quantification method is proposed in this study. The quantification method is compiled with indicators related to the local conditions; these include Emissions, Resource Depletion and Waste Generation. The end objective is to provide the user with an aggregated total value called the Environmental Impact Index to ease comparison of possible alternatives. The quantification method is developed as a mathematical tool in the form of a partial Life Cycle Assessment which can aid in objective decision making during the conception and design phase of a specific project. Note that only the Pre-Use Phase of the building life cycle is considered during the assessment, but can be extended to include the Use Phase and End-of-Life Phase. The proposed method has the capability of calculating and optimising the environmental impact of a building. Regarding low-cost housing, different housing unit designs can be compared in order to select the best alternative. The quantification method is implemented for two low-cost house design types in this study. Firstly, the conventional brick and mortar design is considered whereafter a Light Steel Frame Building is viewed as an alternative. The model implementation demonstrates that the model operates in its supposed manner. Also, Light Steel Frame Building housing units are shown to be worth investigating as an alternative to the conventional brick and mortar design but should be confirmed with a more accurate Life Cycle Assessment.
AFRIKAANSE OPSOMMING: In ’n wêreld waar toenemende ekonomiese en bevolkingsgroei veroorsaak dat al hoe meer kweekhuisgasse voortgebring word, hulpbronne uitgeput word en groter hoeveelhede rommel geproduseer word, is dit ’n bykans onbegonne taak om volhoubaarheid te probeer bereik. Volhoubaarheid rakende die natuurlike omgewing en konstruksie is twee terme wat vandag dikwels saam genoem word. Ongeveer 12.4 % van die kweekhuisgasse wat in Europa vrygestel word kom uit die konstruksie- en vervaardigingbedrywe (Maydl, 2004). Die konstruksiebedryf gebruik ook bykans die helfte van hulpbronne wat ontgin word en meer as 25 % van rommel word deur konstruksie of sloping produseer. Die Suid-Afrikaaanse boubedryf is verantwoordelik vir 23 % van die totale hoeveelheid kweekhuisgasse wat die land vrystel. Die behuisingsektor, waar die regering aan die hoof van 33 % van eenhede staan, ontvang 60 % van bestaande beleggings (Milford, 2009). Dit is dus duidelik dat die boubedryf ’n negatiewe impak op die natuurlike omgewing het en dat dit van groot belang is om dié situasie te verbeter. In die behuisingsektor het lae-koste-behuising groot potensiaal as dit kom by volhoubaarheid. Volhoubaarheid bestaan uit drie sfere: ekonomie, natuurlike omgewing en sosiaal, en al drie speel ’n betekenisvolle rol in lae-koste-behuising. Daar is reeds verskeie studies aangepak om die ekonomiese en sosiale sfere te beskryf, maar daar is steeds min inligting beskikbaar oor die omgewingsimpak van ’n lae-koste-huis. Dit laat die behoefte ontstaan om hierdie impak te kwantifiseer. Bestaande metodes wat wêreldwyd gebruik word om ʼn omgewingsimpak te bepaal is dikwels besonder kompleks en benodig duur sagteware tesame met ingewikkelde databasisse om dit te implementeer. ’n Behoefte aan ’n plaaslike kwantifiseringsmetode is geïdentifiseer. Hierdie studie stel ’n eenvoudige, gebruikersvriendelike kwantifiseringsmetode bekend. Dit word saamgestel uit faktore wat verband hou met die plaaslike omgewing: Uitlaatgasse, Hulpbronuitputting en Rommelvervaardiging. Uiteindelik word ’n saamgestelde waarde, wat die Omgewingsimpak-indeks genoem word, bereken om vergelyking te vergemaklik. Hierdie kwantifiseringsmetode word aan die hand van ’n gedeeltelike lewenssiklus-analise as ’n wiskundige hulpmiddel ontwikkel. Slegs die eerste fase van ’n gebou se lewenssiklus word beskou tydens hierdie studie, maar dit is moontlik om die ander twee fases in te sluit. Die voorgestelde metode het die vermoë om die omgewingsimpak te bereken en ook te optimeer. Tydens die ontwerpsfase, wanneer belangrike besluite geneem moet word, kan so ’n hulpmiddel van enorme waarde wees om die beste opsie uit verskillende alternatiewe te help identifiseer. Die studie beskou twee tipes behuisingseenhede vir die doel van implementering van die kwantifiseringsmetode: die konvensionele baksteen en mortel metode en alternatiewelik ’n ligte staalraamwerk-gebou. Tydens implementering van die voorgestelde metode, demonstreer die model dat dit werk soos dit veronderstel is om te funksioneer. Verder is getoon dat ’n ligte staalraamwerk-gebou ’n waardevolle alternatief is om te ondersoek, maar dit moet liefs met ’n meer akkurate lewenssiklus-analise bevestig word.
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Degerman, Sofie. "The immortalization process of T cells with focus on the regulation of telomere length and telomerase activity /." Doctoral thesis, Umeå : Umeå University, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-33466.
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Broich, Anna Katharina [Verfasser], and George [Akademischer Betreuer] Iliakis. "Systematic analysis of alt-EJ regulation in irradiated cells at the interface of G0/G1 cell cycle phases: focus on growth factor signaling and CtIP / Anna Katharina Broich ; Betreuer: George Iliakis." Duisburg, 2020. http://d-nb.info/1213245567/34.
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Aguinaga, Umeres Angela Zulma, and Hernández Yanira Anahí Pinto. "Qualitative study with a phenomenological focus on the reasons for replacing main meals and choice alternatives, in first and second-cycle students of Architecture at a private university in Lima, Peru 2019." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/656218.
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Briere, Raphaël. "Etude ACV des chantiers de démolition en vue de la préservation des ressources : focus sur les procédés de transport et de décharge." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1003/document.
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La préservation des ressources naturelles est un des enjeux majeurs dans les années à venir. Le secteur de la construction tant par les besoins auxquels il répond que par les ressources qu'il mobilise joue un rôle majeur dans ce challenge. Il est alors pertinent de s'intéresser à la fin de vie de bâtiments dont la gestion permet de potentiellement transformer des déchets en matières premières. A l'aide de l'Analyse de Cycle de Vie, il est possible d'estimer les impacts environnementaux de ces chantiers mais surtout d'estimer les bénéfices possibles d'une gestion plus durable. D'une démolition traditionnelle où le tri des déchets n'était pas ou peu réalisé nous sommes passés vers une démolition plus sélective où les différentes catégories de déchets étaient séparées puis envoyées dans les différentes installations et filières de gestion des déchets (plateforme de recyclage, incinérateurs ou installations de stockage par exemple). Le recyclage des déchets est aujourd'hui favorisé notamment pour des matériaux où les bénéfices environnementaux rejoignent ceux économiques comme les métaux. Notre travail a envisagé la réutilisation d'éléments structurels en béton armé en lieu et place d'un recyclage afin d'allonger leur durée de vie et de diminuer les besoins en ressources minérales. La pertinence environnementale de cette solution alternative a été ainsi regardée. Une deuxième contribution se situe au niveau de l'adaptation de données. Dans les différentes analyses ACV menées tout au long de cette thèse, la base Ecoinvent a été utilisée. Cependant, les données fournies sont souvent moyennées ce qui diminue la pertinence de leur utilisation dans un cas spécifique. Le procédé de transport par camion ainsi que celui de mise en décharge ont été étudiés de manière approfondie afin de les adapter à notre cas spécifique des chantiers de démolition situés en France. Dans le cas du transport, il a été nécessaire d'intégrer le retour à vide des camions évacuant les déchets tandis que les installations de stockage françaises ont des infrastructures différentes des décharges de référence suisses. Ainsi, ce travail d'adaptation des données Ecoinvent pourrait être étendue à d'autres modules de transports ou de décharges mais également à d'autres modules Ecoinvent afin de renforcer la pertinence des études ACVThe preservation of natural ressources is one of the biggest concerns for the years to come. The building sector that fulfills the need of a housing for every human being requires a lot of materials. Indeed, this industry plays a crucial role. Then, it seems relevant to study the building end of life which managing can transform waste into ressources. Thanks to the Life Cycle Assessment, it is possible to evaluate the environmental impacts of demolition sites and also to estimate the potential benefits of a more durable managing. From a traditional demolition where waste separation was not or little done, we are now going to a selective demolition where waste sorting is made and the different waste categories are sent to specific installations (recycling platforms, incinerators or landfills for example). Nowadays, waste recyling is being encouraged particularly for materials where the environmental benefits come with the economic ones like for metals. Our work considered the reuse of structural elements in reinforced concrete instead of their recycling. It allows to increase their lifetime while decreasing the need in mineral ressources. The environmental relevance of this solution was studied. The second contribution deals with the data adaptation needed in LCA. During the various LCA studies done in this work, the Ecoinvent database was used. However, the provided data was often too aggregated and consisted in average data which reduces the relevance of using it in specific cases. A deep analysis of the truck transportation and the landfill processes was made as well as the adaptation needed to be coherent with the specific case of demolition sites located in France. In the case of the transport process, the empty returns were more specifically taken into account. For the landfill process, one has to deal with the differences between the french and the swiss infrastructures used as the reference ones. Thus, this data adaptation could be extended to other transport and landfill processes but also to other Ecoinvent processes in order to reinforce the reliability of LCA studies
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Possan, Edna. "Modelagem da carbonatação e previsão de vida útil de estruturas de concreto em ambiente urbano." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/28923.
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Este trabalho propõe um modelo matemático destinado à estimativa da profundidade de carbonatação e à previsão de vida útil de projeto de estruturas de concreto, envolvendo variáveis de entrada de fácil obtenção (como resistência à compressão, tipo de cimento, umidade relativa, entre outras). Com base no conhecimento de experts (grupo focal) criou-se o banco de dados que deu origem ao modelo, o qual considera as principais variáveis de influência na ação da carbonatação, incluindo: às características do concreto (resistência à compressão do concreto aos 28 dias, o tipo de cimento empregado, o teor de adição, quando houver); às condições de exposição (macro clima - ambiente interno ou externo, protegido ou não da chuva); e, às condições ambientais (umidade relativa média da região de exposição da estrutura e o teor de CO2 do ambiente). O modelo matemático proposto baseou-se no ajuste de dados considerando as leis físico-químicas pertinentes, o qual foi testado com dados de investigações experimentais realizadas por outros pesquisadores. Os resultados indicam que o mesmo representa a ação da carbonatação do concreto, apresentando potencial de generalização. Também foi empregado para a previsão de vida útil de projeto, com uma abordagem probabilística via Simulação de Monte Carlo (SMC) e Análise de confiabilidade, inserindo as variabilidades existentes no processo de degradação. Os resultados das simulações demonstram que o modelo pode ser empregado para estimativa de vida útil via processos estocásticos. O modelo foi desenvolvido essencialmente para servir como um suporte para a análise da durabilidade de estruturas de concreto armado em ambiente urbano, podendo ser empregado tanto para a estimativa da profundidade de carbonatação do concreto quanto para a previsão de vida útil de projeto de estruturas novas ou existentes, com abordagem determinística ou probabilística. As maiores vantagens do modelo são relacionadas à entrada de dados os quais podem ser obtidos com relativa facilidade, à facilidade de aplicação e ao potencial de generalização.This research work proposes a mathematical model to estimate carbonation depths and the service life prediction of concrete structures using easily accessible input variables (such as compressive strength, cement type, relative humidity, etc.). The model was designed using a database which was developed using the knowledge of experts (focus group). This database assesses the main variables that affect carbonation in concrete (compressive strength at 28 days, type of cement, concentration of addition, if applicable), exposure conditions (macroclimate – indoors or outdoors, exposure to rain) and environmental conditions (mean relative humidity and carbon dioxide concentration of the area where the structure is located). The proposed model was tested using experimental data from other researchers and the results suggest that it accurately represents the effects of carbonation in concrete, with results that can be expanded to other structures. The mathematical model was also applied to forecasts of the service life of a project using the probabilistic approach of Monte Carlo methods (MC) and an analysis of reliability that accounted for the intrinsic variability found in decay processes. The results of the simulations show that the model can be used to estimate the service life of a project using a stochastic technique. The model was developed to serve mainly as a supporting feature in the assessment of durability in reinforced concrete structures in urban environments and can be applied both to estimates of carbonation depths and to the service life prediction of projects of new or existing structures, using deterministic or probabilistic approaches. The major benefits offered by this model are related to the input of data, which are readily available, its ease of use and its potential for application in general situations.
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Lazzarotto, Viviana. "Conséquences à long-terme d’une alimentation à base de matières premières végétales sur la régulation du métabolisme énergétique et lipidique chez la truite arc-en-ciel : focus particulier sur les effets trans-générationnels et les stades précoces." Thesis, Pau, 2016. http://www.theses.fr/2016PAUU3002/document.
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Au cours des dernières années, l'augmentation de la production aquacole a nécessité un changement dans la composition des aliments pour poissons, pour remplacer la farine (FP) et l’huile de poisson (HP) par des sources végétales plus disponibles. Dans ce contexte, le travail de ma thèse avait pour but d'analyser les effets d’une substitution totale et concomitante de la FP et HP par des ingrédients végétaux dans les aliments distribués pendant tout le cycle de vie de la truite arc-en-ciel, de la première alimentation jusqu’à la reproduction. Ce travail a montré pour la première fois que la truite peut survivre, se développer et avoir une descendance viable, lorsqu’elle est nourrie tout au long de son cycle de vie avec un régime 100% végétal. Un tel remplacement alimentaire a entraîné des changements radicaux dans le profil en acides gras des tissus des femelles. Cependant, nous avons constaté que la truite était capable de synthétiser des acides gras polyinsaturés à longue chaîne n-3 (AGPI-LC n-3) à partir de précurseurs présents dans l'aliment, et de stocker dans les ovules une partie de ces acides gras néosynthétisés dans le foie , permettant ainsi une reproduction efficace. Nous avons également étudié les possibles effets trans-générationnels d’une alimentation 100% végétale des géniteurs, sur la survie et la croissance de la descendance et sur sa réponse à différents régimes aux stades précoces, en nous appuyant sur des analyses du transcriptome des alevins entiers. Aucun effet significatif de l’alimentation maternelle avec des régimes à base de végétaux n’a été observé sur les descendants avant leur première alimentation, à l'exception d'un poids corporel légèrement inférieur (-13%) à celui des descendants de femelles nourries avec un aliment contenant des FP et HP. En revanche, des effets significatifs de l'alimentation maternelle sur le transcriptome des alevins sont apparus après 3 semaines d'alimentation. L'histoire nutritionnelle de la mère a affecté principalement des gènes impliqués dans la croissance/contraction musculaire et dans les métabolismes énergétique et glucidique. Quelle que soit l'origine maternelle, l’alimentation des alevins avec des aliments contenant des ingrédients végétaux conduit à une régulation positive des gènes impliqués dans le métabolisme des AA/protéines et le métabolisme du cholestérol, ainsi qu’à des changements dans l'expression des gènes impliqués dans le métabolisme glucidique. Enfin, les effets à long-terme de régimes à base de matières premières végétales chez la truite arc-en-ciel ont également été étudiés chez les juvéniles (10g) et les poissons «en croissance» (250-350g), en se focalisant principalement sur l’expression des gènes dans l’intestin et le foie. Cette étude à long-terme a mis en évidence chez les juvéniles des effets subtils sur des gènes intestinaux et hépatiques (transcriptome), avec principalement une augmentation de l’expression des gènes impliqués dans les voies de synthèse des AGPI-LC et du cholestérol chez les poissons nourris avec des régimes à base de plantes. Ces changements d’expression ont été maintenus chez les poissons «en croissance». L'expression de gènes impliqués dans le catabolisme des protéines, le métabolisme des glucides et dans le transport intracellulaire a également été modifiée par les régimes à base de plantes chez les juvéniles, mais ces résultats ne sont pas entièrement confirmés chez les poissons «en croissance». L'ensemble des résultats de cette thèse fournissent des informations originales sur l'utilisation de régimes alimentaires avec des taux de remplacement élevés de FP et d’HP pendant l'ensemble du cycle de vie des poissons, y compris les reproducteurs et les stades précoces, car la majorité des études précédentes avaient concerné la phase de grossissement. Des ajustements de la formule alimentaire sont encore nécessaires pour continuer à optimiser les performances de reproduction et la croissance des poissons d’élevageIn the last years, the increase in aquaculture production has forced a change in fish feed composition, with increasing substitution of fish meal and fish oil by more available plant sources. In this context, the present PhD work aimed at analyzing the effects of different levels of concomitant dietary replacement of fish meal and fish oil by plant ingredients during the whole life cycle of rainbow trout (from first feeding to reproduction). This work showed for the first time that rainbow trout was able to survive, grow and produce viable offsprings, when fed a totally plant-based diet throughout the whole life cycle. Such dietary replacement resulted in drastic changes in tissues fatty acid profile of broodstock females. However, we found that trout was capable to synthetize n-3 long chain- polyunsaturated fatty acids (LC-PUFA) from dietary precursors and to transfer large amounts of these fatty acids in ova, so that an efficient reproduction can occur. We also studied the potential carry over generation effects of feeding broodstock a totally plant-based diet on progeny and their response to different diets at early stages, using molecular approaches, including the study of the whole body transcriptome. Considering the effects on progeny, the present study confirmed the capability of trout to survive and grow on a plant-based diet, but with slight differences in terms of weight. While no effects of maternal dietary background were observed before first feeding, except slightly lower body weight (-13%), significant effects on the transcriptome of whole body alevins appeared after 3 weeks of feeding. These effects of maternal nutritional history were mainly related to muscle growth/contraction and carbohydrate and energy metabolism. Irrespective of the maternal origin of progeny, first feeding diets containing plant ingredients resulted in up-regulation of genes involved in AA/protein and cholesterol metabolism, as well as in changes in the expression of genes involved in carbohydrate metabolism. Finally, the effects of long-term feeding trout plant-based diets were also studied in juveniles (10g) and ongrowing fish (250-350g), mainly focusing on intestine and liver gene expression. The long term trial in juveniles highlighted subtle effects on both intestinal and hepatic gene expression (transcriptome), mainly related to LC-PUFA and cholesterol biosynthetic pathways, which were enhanced in fish fed the plant based diets. This transcriptional pattern was maintained in ongrowing fish. Genes involved in protein catabolism, carbohydrate metabolism and trafficking were also affected by plant-based diets in juveniles, but these results were not fully confirmed in ongrowing fish. Overall, the results of the present thesis allowed extending the use of diets with high replacement rates of fish meal and fish oil to the whole life cycle of fish, including broodstock and early stages. Adjustments of the feed-formula are still needed to further optimize reproductive and growth performance
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Wrammert, Johan. "Surviving birth : Studies of a simplified neonatal resuscitation protocol in a low-income context using a mixed-methods approach." Doctoral thesis, Uppsala universitet, Internationell mödra- och barnhälsovård (IMCH), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316728.
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United Nations has lately stated ambitious health targets for 2030 in the Sustainable Development Goal agenda, following the already achieved progress between 1990 and 2015 when the number of children dying before the age of five was reduced by more than half. However, the mortality reduction in the first month of life after birth has not kept the same pace. Furthermore, a large number of stillbirths have previously not been accounted for. The aim of this thesis was to evaluate the impact of clinical training in neonatal resuscitation, and to identify strategies for an effective implementation at a maternal health facility in Nepal. Focus group discussions were used to explore the perceptions of teamwork among staff working closest to the infant at the facility. A prospective cohort study with nested referents was applied to determine effect on birth outcomes after an intervention with Helping Babies Breathe, a simplified protocol for neonatal resuscitation. Sustainability of the acquired skills after training was addressed by employing a quality improvement cycle. Video recordings of health workers performance were collected to analyse adherence to protocol. Midwives described the need for universal protocols in neonatal resuscitation and management involvement in clinical audit and feedback. There was a reduction of intrapartum stillbirth (aOR 0.46, 95% CI 0.32–0.66) and neonatal mortality within 24 hours of life (aOR 0.51, 95% CI 0.31–0.83) after the intervention. Ventilation of infants increased (OR 2.56, 95% CI 1.67–3.93) and potentially harmful suctioning was reduced (OR 0.13, 95% CI 0.09–0.17). Neonatal death from intrapartum-related complications was reduced and preterm infants survived additional days in the neonatal period after the intervention. Low birth weight was not found to be a predictor of deferred resuscitation in the studied context. This study confirmed the robustness of Helping Babies Breathe as an educational tool for training in neonatal resuscitation. Accompanied with a quality improvement cycle it reduced intrapartum stillbirth and mortality on the day of delivery in a low-income facility setting. Improved postnatal care is needed to maintain the gains in survival through the neonatal period. Increased management involvement in audit and quality of care could improve clinical performance among health workers.
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Elfving, Anna. "Transcriptional regulation of mouse ribonucleotide reductase." Licentiate thesis, Umeå universitet, Institutionen för medicinsk kemi och biofysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-41272.
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All living organisms are made of cells and they store their hereditary information in the form of double stranded DNA. In all organisms DNA replication and repair is essential for cell division and cell survival. These processes require deoxyribonucleotides (dNTPs), the building blocks of DNA. Ribonucleotide reductase (RNR) is catalyzing the rate limiting step in the de novo synthesis of dNTPs. Active RNR is a heterodimeric protein complex. In S phase cells, the mouse RNR consists of the R1 and the R2 proteins. The R1/R2 RNR-complex supplies the cell with dNTPs required for DNA replication. Outside S-phase or in non-proliferating cells RNR is composed of R1 and p53R2 proteins. The R1/p53R2 RNR-complex supplies cells with dNTPs required for mitochondrial DNA replication and for DNA repair. An undisturbed dNTP regulation is important since unbalanced dNTP pools results in DNA mutations and cell death. Since unbalanced pools are harmful to the cell, RNR activity is regulated at many levels. The aim of this thesis is to study how the mouse RNR genes are regulated at a transcriptional level. We have focused on the promoter regions of all three mouse RNR genes. Primer extension experiments show that the transcription start of the TATA-less p53R2 promoter colocalizes with an earlier unidentified initiator element (Inr-element). This element is similar to the known Inr-element in the mouse R1 promoter. Furthermore, functional studies of the R1 promoter revealed a putative E2F binding element. This result suggests that the S phase specific transcription of the R1 gene is regulated by a similar mechanism as the R2 promoter which contains an E2F binding site. Finally we have established a method to partially purify the transcription factor(s) binding the upstream activating region in the mouse R2 promoter by phosphocellulose chromatography and affinity purification using oligonucleotides immobilized on magnetic beads. This method will allow us to further study the transcription factors responsible for activating expression of the R2 protein. This method has a potential to be utilized as a general method when purifying unknown transcription factors.
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Rosenblatt, Suzana Mester. "O processo de decisão do cliente de alta renda na aquisição de imóveis residenciais na cidade de São Paulo." reponame:Repositório Institucional do FGV, 2008. http://hdl.handle.net/10438/5518.
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Previous issue date: 2008-03-28T00:00:00ZThis dissertation is an exploratory study of the decision making process in the acquisition of residential real estate by the high income consumer at the city of São Paulo. The work looks first at the literature to explain the importance of client focus and the understanding of his acquisition decision process as a source of competitive advantage. After that, trough personal interviews with twelve individuais from the targeted group that have bought apartments no longer than three years before, it searches for evidences of their acquisition decision process and elements that allow us to get a better knowledge of the attributes that have value for them and are responsible for the success or the failure of a new development. Through the interviews the findings were: the recognition of the problems comes with uncomfortable feelings due to changes in the family life cycle, the most relevant attributes were: local area, finance conditions andapartment layout , the search for information was done mainly trough visits to the neighborhood, the family had great influence in the decision of the purchase, the choice between alternatives was made based on the levei of importance given to different atlributes, and the search for satisfaction was immediate. As counter points to satisfaction, were mentioned: small parking lots, low concern with security at the project fase, neither equipped nor decorated common areas of the building, and lack of air conditioning infra-estructure. Based on these results this work concludes that there is an opportunity for real estate companies that not yet have client focus, to implement a direct channel of communication with the client for the understanding of their needs and desires and to use these information to gain competitive advantage.
O trabalho investiga, de modo exploratório, o processo de decisão de compra de um imóvel residencial pelo público de alta renda na cidade de São Paulo. Para tal, este estudo parte da literatura para indicar a importância do posicionamento estratégico de foco no cliente e da compreensão do seu processo de tomada de decisão de compra, como fonte de vantagem competitiva. Segue então uma etapa de campo na qual são realizadas entrevistas em profundidade com doze indivíduos do publico alvo que compraram apartamento em período não superior a três anos, em busca de evidências de como se dá o seu processo de decisão de compra e dos atributos por eles valorizados, responsáveis pelo sucesso ou insucesso de um novo empreendimento imobiliário. Através das entrevistas, pudemos perceber que: o reconhecimento do problema se deu primordialmente através de estados de desconforto função de alterações no ciclo de vida da família; os atributos mais relevantes foram: localização, condições de financiamento e programa interno do apartamento; a busca por informações se deu principalmente através de visitas à região de interesse; a família teve grande influência na compra; a avaliação de alternativas foi feita em função do grau de importância dado aos diferentes atributos; e, uma vez identificada à necessidade, procurou-se satisfazê-Ia de forma imediata. Como pontos de insatisfação foram referidos: área de garagem pequena, entrega do apartamento sem as áreas comuns equipadas e decoradas, pouca preocupação com segurança na etapa de projeto e falta de tubulação de ar condicionado. Com base nos resultados encontrados, este trabalho conclui que existe oportunidade para empresas do ramo de incorporação imobiliária que ainda não possuem foco no cliente, de estabelecer um canal de comunicação direto com os clientes para compreensão das suas necessidades e desejos, e utilizar tais informações para ganhar vantagem competitiva.
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Badran, Ghidaa. "Pollution atmosphérique particulaire : caractérisation physico-chimique et comparaison des effets toxiques des fractions extractible et non-extractible des PM₂.₅ In-vitro evaluation of organic extractable matter from ambient PM₂.₅ using human bronchial epithelial BEAS-2B cells : Cytotoxicity, oxidative stress, pro-inflammatory response, genotoxicity, and cell cycle deregulation. Toxicity of fine and quasi-ultrafine particles : focus on the effects of organic extractable and non-extractable matter fractions. Toxicological appraisal of the chemical fractions of ambient fine (PM₂.₅-₀.₃) and quasi-ultrafine (PM₀.₃) particles in human bronchial epithelial BEAS-2B cells." Thesis, Littoral, 2019. http://www.theses.fr/2019DUNK0547.
Full textAbstract:
La pollution de l'air et les particules fines (PM₂.₅) ont été classées cancérigènes (groupe 1) par le Centre International de la Recherche sur le Cancer en 2013. Cette fraction particulaire représente un mélange complexe dont la composition, très variable, influe sur la toxicité. Cependant, peu d'études ont déterminé l'implication respective des différentes fractions chimiques constitutives des PM dans leurs effets toxiques. Dans ce travail de thèse, des particules fines (PM₂.₅₋₀.₃) et quasi-ultrafines (PM₀.₃) ont été échantillonnées au niveau d'un site urbain à Beyrouth (Liban). Après avoir réalisé la caractérisation physico-chimique de ces deux types de particules, leurs effets toxiques (cytotoxicité globale, activation métabolique, génotoxicité, inflammation, stress oxydant, autophagie et apoptose) ont été étudiés sur une lignée de cellules épithéliales bronchiques humaines (BEAS-2B). L'analyse des fractions organiques a révélé des différences entre les teneurs en hydrocarbures aromatiques polycycliques (HAP), de même qu'en congénères oxygénés (O-HAP) et nitrés (N-HAP), respectivement 43, 17 et 4 fois plus élevées dans les PM₀.₃ que dans les PM₂.₅₋₀.₃. L'étude toxicologique a porté sur les particules fines considérées dans leur entièreté (PM₂.₅₋₀.₃), la fraction organique extractible (EOM₂.₅₋₀.₃) et la fraction non-extractible par le dichlorométhane (NEM₂.₅₋₀.₃). De plus, les effets spécifiques de la fraction organique extraite des particules quasi-ultrafines (EOM₀.₃) ont été comparés à ceux de la fraction organique extraite des particules fines (EOM₂.₅₋₀.₃). Nos résultats montrent que chacune des fractions considérées a été capable d'activer au moins un des mécanismes étudiés. Les PM₂.₅₋₀.₃ ont induit des effets toxiques généralement plus marqués que les EOM₂.₅₋₀.₃ et NEM₂.₅₋₀.₃. La fraction organique des particules quasi-ultrafines (EOM₀.₃), plus riche en composés organiques et notamment en HAP et autres congénères, est apparue responsable d'effets délétères globalement plus importants que celle extraite des particules fines (EOM₂.₅₋₀.₃). Les résultats de ce travail ont apporté des éléments nouveaux sur la toxicité relative des différentes fractions extractibles et non extractibles des particules fines et soulignent le rôle crucial joué par les particules ultrafines, encore trop peu étudiéesAir pollution and particulate matter (PM₂.₅) were classified as carcinigens (group 1) by the International Agency for Research on Cancer in 2013. This particulate fraction represents a complex mixture with a highly variable composition influencing the toxicity. However, few studies have determined the respective involvement of the different chemical fractions of PM in their toxic effects. In this work, fine particles (PM₂.₅₋₀.₃) and quasi-ultrafine particles (PM₀.₃) were sampled in an urban site located in Beirut (Lebanon). After performing the physicochemical characterization of these two types of particles, their toxic effects (global cytotoxicity, metabolic activation, genotoxicity, inflammation, oxidative stress, autophagy and apoptosis) were investigated on a human bronchial epithelial cell line (BEAS-2B). The analysis of the organic content revealed differences between the concentrations of polycyclic aromatic hydrocarbons (PAHs), as welle as oxygenated (O-PAH) and nitrated (N-PAH) congeners, respectively 43, 17 and 4 times higher in PM₀.₃ than in PM₂.₅₋₀.₃.The toxicological study was based on the comparison of the toxicity of the fine particles considered in their entirety (PM₂.₅₋₀.₃), the extracted organic fraction (OEM₂.₅₋₀.₃) and the fraction not extracted by the dichloromethane (NEM₂.₅₋₀.₃). In addition, the specific effects of the organic fraction extrated from the quasi-ultrafine particles (OEM₀.₃) were compared with those of the organic fraction extracted from the fine particles (OEM₂.₅₋₀.₃). Our results showed that all the studied fractions were able to induce at least one of the studied mechanisms. PM₂.₅₋₀.₃ was able to induce toxic effects greater than those induced by OEM₂.₅₋₀.₃ and NEM₂.₅₋₀.₃. The organic fraction extracted from the quasi-ultrafine particles (OEM₀.₃), richer in organic compounds and in particular in PAHs and other congeners, appeared to be responsible for deleterious effects globally greater than that extracted from the fine particles (OEM₂.₅₋₀.₃). The results of this work have brought new elements on the relative toxicity of the different fractions of the fine particles and underline the crucial role played by ultrafine particles, still too little studied
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Liang, Chih-kuo, and 梁治國. "Manager Focus Adjustment Through Enterprise Life Cycle :Using a Semiconductor Company As An Example." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/67559139940644182103.
Full textAbstract:
碩士國立交通大學
高階主管管理學程碩士班
92
This thesis is a case study to collect the related information, experiences, and documentation about the possible problems of an enterprise due to its current position among different lifecycle stages. In addition, the thesis concludes the reactions and benefits managers should adjust their focus according to the possible problems through the enterprise lifecycles. The study shows that the management focuses in infancy stage are discipline of execution, control cash flow, and resource focus. The management focuses in go-go stage are careful investment, build organizational system, and enhance management team. The management focuses in adolescence stage are avoiding conflict, build operational system, and build corporate direction and vision. The management focuses in prime stage are develop new business, expand-integrate-expand, business process re-engineering, and build core competence. The management focuses in stable stage are create crisis sense, stimulate innovation, develop new market and new product, allow mistake and avoid conservativeness. The management focuses in aristocracy stage are break tradition, enhance new business, and avoid waste and luxury. The maThe thesis also gives suggestions about the needed management skills for different lifecycle stages. In growing stages, the professional skills of execution, core competence, and human-centered IT management are needed. In prime stage, skills of innovation, strategic alliance, corporate merger and acquisition are needed. The stable stage is the turning point between growing stages and aging stages and the skills of change and innovation are needed. In aging stages, management should try change, innovation, and business process re-engineering to change the situation and look for the opportunity of creating a new lifecycle.nagement focuses in early bureaucracy stage are establishing change committee and corporate re-engineering. The management focus in bureaucracy stage is re-organization.
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Madzivhandila, Vhutshilo. "Clean coal technology using process integration : a focus on the IGCC." Diss., 2011. http://hdl.handle.net/2263/28877.
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The integrated gasification combined cycle (IGCC) is the most environmentally friendly coal-fired power generation technology that offers near zero green house gas emissions. This technology has higher thermal efficiency compared to conventional coal-fired power generation plants and uses up to 50% less water. This work involves the optimization of IGCC power plants by applying process integration techniques to maximize the use of energy available within the plant. The basis of this project was the theoretical investigations which showed that optimally designed and operated IGCC plants can achieve overall thermal efficiencies in the regions of 60%. None of the current operating IGCC plants approach this overall thermal efficiency, with the largest capacity plant attaining 47%. A common characteristic in most of these IGCC plants is that an appreciable amount of energy available within the system is lost to the environment through cold utility, and through plant irreversibility to a smaller extent. This work focuses on the recovery of energy, that is traditionally lost as cold utility, through application of proven process integration techniques. The methodology developed comprises of two primary energy optimization techniques, i.e. pinch analysis and the contact economizer system. The idea behind using pinch analysis was to target for the maximum steam flowrate, which will in turn improve the power output of the steam turbine. An increase in the steam turbine power output should result in an increase in the overall thermal efficiency of the plant. The contact economizer system is responsible for the recovery of low potential heat from the gas turbine exhaust en route to the stack to heat up the boiler feed water (BFW). It was proven in this work that a higher BFW enthalpy results in a higher overall efficiency of the plant. A case study on the Elcogas plant illustrated that the developed method is capable of increasing the gross efficiency from 47% to 55%. This increase in efficiency, however, comes at an expense of increased heat exchange area required to exchange the extra heat that was not utilized in the preliminary design.Dissertation (MEng)--University of Pretoria, 2011.
Chemical Engineering
unrestricted
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Romano, Elisa. "Factors associated with the sexual abuse cycle : a focus on perpetrators with histories of sexual abuse." 1994. http://hdl.handle.net/1993/18439.
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Lu, Ling-chen, and 盧玲甄. "Research on "Zhou-yi" Hexagram Change Cycle Thinking─Focus on the Twelve Yin-Young Growing Hexagrams." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/32302925489453510088.
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碩士世新大學
中國文學研究所
99
"Zhou-yi"the cycle of yin and yang duality can be reflected in the transactions are in time and place / space, staggered under the conditions of the full show. Therefore, this paper wishes to news by hexagrams between yin and yang, and the 64 hexagrams hexagram change the interpretation, to deduce a "Book of Changes" hexagrams unique circulatory system, and this cycle of the Earth system and the real space coordinates match, the establishment of hexagrams unique three-dimensional model of follow-change cycle, the "Book of Changes" hexagrams three hundred eighty-four Yao coordinates of the Earth in real time and space, to find each hexagrams are "bit", to comply should be Heaven line does not run the week of the natural trajectory of Scots, as I settle down criteria. This study approaches, the message is twelve Gua Gua change cycle as the core, the first theory, "" Book of Changes "Gua variable cycle" in the name of "Zhou-yi" "when", "position", "life" of three propositions cycle thinking, "Gua qi said," and "two two-phase coupling, which becomes non-covered" two Gua change form, as Gua variable cycle thinking leads. Second, the message will be 12 hexagrams as "Book of Changes" hexagrams of the circulatory system based model analysis of the changes inherent in the form of four hexagrams, in order: First, a Gua Liu Yao internal circulation; Second, the cover abandoned the group between cycles; three interest rate and consumption Gua Gua Gua group cycle; four, twelve news hexagram as a whole cycle. And after twelve cycles of yin and yang hexagram structure of the message, in, the push from successive days with the yin and yang gossip circulating form; from the next, pushing the overall performance hexagrams message loop system, whereby the layers of interpretation, construct hexagrams unique circulation spiral form to reflect the "easy" road since the days of the people, endless, and finally there are the beginning of the cycle of thinking.
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Trask, Samantha Leigh. "Up | down | re [CYCLE] infrastructure for integrated waste management a focus on informal trolley pushers in Newtown, Johannesburg." Thesis, 2014. http://hdl.handle.net/10210/9675.
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M.Tech. (Architectural Technology)The City of Johannesburg has no formal recycling strategy and waste is simply dumped as collected in designated landfill sites. Yet these landfill sites, reportedly, will be good for no more than another eight years. Throughout the city there is an informal network of waste collectors commonly known as trolley pushers who, together with the private buy-back and recycle centres, form the only real system of recycling in Johannesburg. There is no infrastructure for the trolley pushers, men and women who perform a vital function. There are no dedicated spaces and very little tolerance from the residents of Johannesburg. The trolley pushers sleep amongst their collection of waste, or travel far to start each day in the very early hours of the morning. They roll their improvised trolleys full of goods in the street among the traffic of commuters, hindering and being hindered. They store their messy waste, when they can in unsafe and public spaces, such as under bridges and on the side of some roads. Storage is such a problem for trolley pushers that often they’re forced to sell their goods as soon as they collect them, when the fluctuating prices may be too low. They are always essentially at the mercy of the privately-owned buyback centres. Their days are long and they have no ablution facilities, no designated space to catch their breath, eat, obtain drinking water, network or socialise. This project is about changing that by facilitating the informal recycling sector, providing the convenient infrastructure without formalising the process. The term ‘convenient’ in this context encompasses spaces close to the buy-back centre, with low tech, low maintenance, mixed-use facilities. These facilities include secure sorting and storage spaces, sleeping, ablution and social spaces. The essence of this project is to encourage, empower and improve work and income potential in the informal waste recycling sector through simple, appropriate architectural interventions that are essentially selfmaintaining.
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JoelCubol and 古博而. "Concerting Development Strategies of Nations Linked by a Product Life Cycle: An Example in Promotion of Future Vehicle Industries with Focus on Resource Management." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/c3dxyc.
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碩士國立成功大學
環境工程學系碩博士班
101
Electric and hybrid vehicle industry is one of those strategically promoted in Taiwan expected to provide domestic and international markets with parts and final products contributing to Taiwanese economy in the next decades. Such strategy must be in concert with strategies on the resource mining countries, assuring economic and environmental sustainability among the nations involved. In this study, Taiwan’s lithium (Li) and nickel (Ni) demands until 2060 are estimated in accordance to the promotion plans of the introduction of electric vehicles in the country. This new vehicle industry would utilize these critical metal resources as key components of the batteries. When these metals exit from the market as reusable resource, it is aimed to create a metal recycling industry in Taiwan. Given the recycling participation of the disposed batteries and the efficiency to recover nickel and lithium, the ultimate potential in recycled metal supply and the mined metals to supplement the shortage to the metal demand can be estimated. These information together with the associated GHG emission are the key inputs to the concerted roadmaps of technological and resource management strategies of Taiwan and the mining countries – Bolivia and the Philippines – that is proposed in this study. With the increasing number of EVs, although this development plan is coupled with the improvement in battery technology in terms of decreasing the metal intensity, the projection still shows an increasing to slowly saturating metal demands. Because of this, disposed metal stocks accumulation in Taiwan has also increasing trend, making them capable of becoming self-sufficient in supplying its own demand by recycling these disposed metal stocks. This, however, induces more GHG emission from Taiwan and limits the supply share of mining countries. This may sound beneficial in terms of minimizing GHG emission in mining countries; however, it poses challenges in economic aspects of sustainability. If the mining countries cannot achieve economic sustainability, the product life cycle cannot be sustainable. Hence, it is suggested that while the demand from the mining countries is still not suppressed by Taiwan’s recycling industry, they can establish other industry such as downstream processing and refining to increase the economic value of their resource. The demonstrated example of concerting development strategies of the three stakeholders may not be, however, realistic enough. In reality, these countries interact to more countries and not only linked by one technology or product. Thus, it is recommended for future studies to add more stakeholders and more products to link them to make the model more dynamic and more realistic.
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(9746375), Timothy Simon. "A Study of Additive manufacturing Consumption, Emission, and Overall Impact With a Focus on Fused Deposition Modeling." Thesis, 2021.
Find full textAbstract:
Additive manufacturing (AM) can be an advantageous substitute to various traditional manufacturing techniques. Due to the ability to rapidly create products, AM has been traditionally used to prototype more efficiently. As the industry has progressed, however, use cases have gone beyond prototyping into production of complex parts with unique geometries. Amongst the most popular of AM processes is fused deposition modeling (FDM). FDM fabricates products through an extrusion technique where plastic filament is heated to the glass transition temperature and extruded layer by layer onto a build platform to construct the desired part. The purpose of this research is to elaborate on the potential of this technology, while considering environmental impact as it becomes more widespread throughout industry, research, and academia.
Although AM consumes resources more conservatively than traditional methodologies, it is not free from having environmental impacts. Several studies have shown that additive manufacturing can affect human and environmental health by emitting particles of a dynamic size range into the surrounding environment during a print. To begin this study, chapters investigate emission profiles and characterization of emissions from FDM 3D printers with the intention of developing a better understanding of the impact from such devices. Background work is done to confirm the occurrence of particle emission from FDM using acrylonitrile butadiene styrene (ABS) plastic filament. An aluminum bodied 3D printer is enclosed in a chamber and placed in a Class 1 cleanroom where measurements are conducted using high temporal resolution electrical low-pressure impactor (ELPI), scanning mobility particle sizer (SMPS), and optical particle sizer (OPS), which combined measure particles of a size range 6-500nm. Tests were done using the NIST standard test part and a honeycomb infill cube. Results from this study show that particle emissions are closely related to filament residence time in the extruder while less related to extruding speed. An initial spike of particle concentration is observed immediately after printing, which is likely a result of the long time required to heat the extruder and bed to the desired temperature. Upon conclusion of this study, it is theorized that particles may be formed through vapor condensation and coagulation after being released into the surrounding environment.
With confirmation of FDM ultrafine particle emission at notable concentrations, an effort was consequently placed on diagnosing the primary cause of emission and energy consumption based on developed hypotheses. Experimental data suggests that particle emission is mainly the result of condensing and agglomerating semi-volatile organic compounds. The initial emission spike occurs when there is dripping of semi-liquid filament from the heated nozzle and/or residue left in the nozzle between prints; this supports the previously stated hypothesis regarding residence time. However, the study shows that while printing speed and material flow influence particle emission rate, the effects from these factors are relatively insignificant. Power profile analysis indicates that print bed heating and component temperature maintaining are the leading contributors to energy consumption for FDM printers, making time the primary variable driving energy input.
To better understand the severity of FDM emissions, further investigation is necessary to diligence the makeup of the process output flows. By collecting exhaust discharge from a Makerbot Replicator 2x printing ABS filament and diffusing it through a type 1 water solution, we are able to investigate the chemical makeup of these compounds. Additional exploration is done by performing a filament wash to investigate emissions that may already be present before extrusion. Using solid phase micro-extraction, contaminants are studied using gas chromatography mass spectrometry (GCMS) thermal desorption. Characterization of the collected emission offers more comprehensive knowledge of the environmental and human health impacts of this AM process.
Classification of the environmental performance of various manufacturing technologies can be achieved by analyzing their input and output material, as well as energy flows. The unit process life cycle inventory (UPLCI) is a proficient approach to developing reusable models capable of calculating these flows. The UPLCI models can be connected to estimate the total material and energy consumption of, and emissions from, product manufacturing based on a process plan. The final chapter focuses on using the knowledge gained from this work in developing UPLCI model methodology for FDM, and applying it further to the second most widely used AM process: stereolithography (SLA). The model created for the FDM study considers material input/output flows from ABS plastic filament. Energy input/output flows come from the running printer, step motors, heated build plate, and heated extruder. SLA also fabricates parts layer by layer, but by the use of a photosensitive liquid resin which solidifies when cured under the exposure of ultraviolet light. Model material input/output flows are sourced from the photosensitive liquid resin, while energy input/output flows are generated from (i) the projector used as the ultraviolet light source and (ii) the step motors. As shown in this work, energy flow is mostly time dependent; material flows, on the other hand, rely more on the nature of the fabrication process. While a focus on FDM is asserted throughout this study, the developed UPLCI models show how conclusions drawn from this work can be applied to different forms of AM processes in future work.