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Challenges and constraints encountered by women and midwives during childbirth in low-income countries : experiences from Angola and MozambiqueOdberg Pettersson, Karen January 2004 (has links)
This thesis aimed to study the actual and perceived quality of midwifery practices during childbirth at peripheral and central health care levels in two low-income countries, Angola (I-III) and Mozambique (IV-V). Theoretical models interpreting women's and midwives' views have been developed. Objectives: Study I evaluates midwives' use of an adapted model of the World Health Organization's partograph, a tool used to monitor the progress of labour. Study II describes midwives experiences of working without immediate medical assistance. Study III explores women's perceptions of care-seeking behaviour during childbirth. Study IV observes perinatal midwifery care routines and examine partograph documentation. Study V explores and develops a theoretical understanding of factors perceived to obstruct or facilitate midwives ability to provide quality of perinatal care. Methods: Study I: A one-group pre-and post-test interventional evaluation of 100 partographs from one peripheral delivery unit. Study II: Semi structured interviews with eleven midwives, analysed in a qualitative process comprising six steps. Study III. Ten focus group discussions with pregnant and non-pregnant women, analysed using the grounded theory technique. Study IV. Pre-and post intervention observation of midwifery care of 702 vs. 616 women during delivery and examination of the partographs. Study V: In-depth interviews with 16 midwives, analysed using grounded theory technique. Educational interventions were designed and applied in study II and IV. Results: Study I. Significant improvement of documenting was found in seven of the ten variables and more partographs were correctly documented in sample II compared to sample I. Missed transfers increased, however, in sample II. Study II: The midwives experiences were sorted under four main areas: (1) Society/culture (2) Significant Others (3) Personal Self (4) Professional Self. Confidence was felt in the role as autonomous midwives but dependency on various factors such as the partograph, a functional referral system, peer support, community trust and continuous supervision was emphasised. Socio-economic hardships were identified as major stress factors for themselves and the women. Study III: Women seemed compelled to "mould" their care seeking behaviour and four patterns, two 'avoiding' and two 'approaching' institutional care were identified. The salient features of each pattern were found to be "personal courage", [B1]"disempowerment", "discarding traditional practices" and "awareness and emancipation". Study IV. No improvements were found in quality of care following the intervention. Common problems proved to be hypothermia and rare initiation of the graphic part of the partograph, which monitors progress of labour. Study V. A process labelled "changing perinatal care management" emerged, which comprised four dimensions addressing aspects related to i) existing environment ii) midwives' interaction with women in labour, iii) midwifery profession and iv) caring technology in order to improve quality of care. Communication and collaboration were identified as change agents. Conclusions: The findings in this thesis indicate that midwives' ability to provide quality of maternal and perinatal care in lowincome and post-war affected countries is restricted by organizational, structural, educational as well as attitudinal aspects. Women in need of assistance during childbirth are negatively affected as a consequence of midwives reaction to the various constraints, which at times (Luanda) seems to oblige adverse care seeking behaviour. Midwives recognises the need for change, but change is found to be a slow and complex process, which requires engagement by all levels of the care chain. A model suggesting how to achieve quality of maternal and perinatal care in Safe Motherhood context is presented.
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A holistic approach to injection moulding optimisation for product quality and cost through the characterisation of reprocessed polymeric materials and process monitoring : experimental evaluations and statistical analysis of multiple reprocessing of unfilled and short glass fibre filled polypropylene materials : an optimised methodology to realise minimum product cost at an acceptable product qualityElsheikhi, Salah A. January 2011 (has links)
The plastics industry is one of the fastest growing major industries in the world. There is an increase in the amount of plastic used for all types of products due to its light weight and ability to reprocess. For this reason, the reprocessing of thermoplastics and the usability of reprocessed materials are gaining significance, and it is important to produce and consume plastic materials in an environmentally friendly way. In addition, rising raw material cost linked to the increased oil prices encouraged for reusing of the plastic materials. The aim of this research was to study and optimize the injection moulding process parameters to achieve a trade-off between the product cost and product quality, measured through mechanical properties and geometry, based on using regrind ratios. The work was underpinned by a comprehensive study of multiple reprocessing effects in order to evaluate the effect of process parameters, material behaviour, reprocessing effects and possible links between the processing parameters and key properties. Experimental investigations were carried out, in particular, focused on the melt preparation phase to identify key process parameters and settings. Multiple reprocessing stages were carried out; using two types of PP material: unfilled and short glass filled. A series of tests were used to examine product quality (mass, colour and shrinkage) and physical properties (density, crystallinity, thermal stability, fibre length, molecular weight, in-line and off-line viscosity, tensile strength, modulus of elasticity, elongation (%) and flexural strength). This investigation showed that the mouldability of the filled and unfilled PP materials, through the successive reprocessing stages (using 100 % regrind), was observed to be relatively consistent. Given the link between the processing parameters and key product and material properties, it is possible to manufacture products with minimal loss to part quality and mechanical properties. The final phase of the work focused on process optimisation study for short glass fibre filled PP material and the identified key process parameters (melt temperature, screw rotational speed, holding pressure, holding time and injection rate). A response surface experiment was planned and carried out for three reprocessing stages (0 %, 25 % and 50 % regrind). The fitted response surface models were utilised to carry out the trade-off analysis between the operating cost (material cost, energy cost and labour cost) and product quality (dimensions and tensile strength) Based on the optimal moulding conditions, the operating cost was reduced (from stage I as a reference), by 24% and 30 % for stage II and stage III respectively. A small, perhaps undetectable, change in product dimensions was noted. In addition, a small reduction in tensile strength was noted (from stage I as a reference), by 0.4% and 0.1 % for stage II and stage III respectively. The same data was applied in other countries (Australia, USA, Brazil, Libya and China) to manufacture the same product; and it was observed that the cost was reduced with increasing of regrind ratio. But the significant reduction of the cost, essentially, depended on those countries which have low wage rates (e.g. Brazil, Libya and China). For example, the cost of moulded product manufactured in China is £ 0.025 (using 50% of regrind), while the cost of the same product produced in Australia is £ 0.12, hence giving a total saving of 79 % and making it a valuable issue to be considered in industry.
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Le décor architectonique de l’Arles antique / The architectural decoration of Ancient ArlesBartette, Titien 16 December 2013 (has links)
Le décor architectonique de l’Arles antique traite de l’ensemble des éléments lapidaires d’architecture décorés de l’antique Arelate. La prise en compte du plus grand nombre de bloc a permis de proposer une synthèse sur l’évolution stylistique et chronologique de l’ornementation arlésienne – une frise qui s’étale du premier triumvirat au Vème siècle après J.-C. – et une restitution du développement architectural du centre monumental d’Arles. L’étude s’articule autour des deux principaux axes analytiques que sont les motifs ornementaux canoniques constitutifs de la modénature des blocs et les composantes architecturales. Par ces analyses, l’objectif premier était de fixer un certain nombre de jalons chronologiques qui pourront faire office de référence en Narbonnaise pour la datation d’éléments d’architecture. Notre raisonnement et les méthodes employées avaient vocation à répondre à une problématique générale qui était la place d’Arles au sein de la Gaule Narbonnaise, notamment par la définition ou la précision de la circulation des cartons et les rapports entretenus avec Rome. Arelate présente toutes les caractéristiques d’une ville ayant brillamment réussi la transposition des « modèles romains », adaptée à son urbanisme et à sa topographie. Rome, et Auguste particulièrement, ont marqué de leur empreinte la ville par les mutations qu’ils ont favorisées et encouragées, à moins qu’ils ne les aient simplement décidées. Ces premiers aménagements sont suivis, au fil des années, de réalisations confirmant le rôle de la colonie dans un processus de romanisation passant en grande partie par l’architecture et le développement de son ornementation. / The architectural decoration of ancient Arles concerns all lapidary decorated architectural elements of Ancient Arelate. Taking into account the largest number of blocks allowed us to propose a synthesis of the stylistic and chronological evolution of Arles ornamentation - a frieze which runs from the first triumvirate to the fifth century AD - and restitution of architectural development of the monumental center of Arles. The study focuses on two main analytical axes, canonical ornaments and architectural components. For these analyses, the primary objective was to fix a number of historical milestones that will serve as a reference for dating Narbonese architectural elements. Our reasoning and methods used were intended to respond to a problem that was the place of Arles in Narbonese Gaul, including the definition or the accuracy of the movement of canonicals ornaments and relationships maintained with Rome. Arelate has all the characteristics of a city having succeeded in the implementation of the "Roman models", adapted to its town planning and its topography. Rome and Augustus in particular have left their mark on the city by the mutations that they fostered and encouraged, unless they simply decided on them. These early developments were followed, over the years, by achievements confirming the role of the colony in a process of Romanization passing largely by the architecture and the development of its ornamentation.
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Etude et modélisation de la cristallisation du Polylactide (PLA) en vue de l'optimisation du procédé de rotomoulage / Polylactic acid (PLA) crystallisation study and modeling for rotomolding process optimizationAressy, Matthieu 19 December 2013 (has links)
Le rotomoulage est une technique de transformation des polymères thermoplastiques qui souffre encore aujourd'hui d'un certain empirisme. Depuis de nombreuses années, la simulation du procédé de rotomoulage est considérée comme une nécessité à l'introduction de nouveaux matériaux et à l'élargissement de ses domaines applications. Ces travaux s'inscrivent à la suite de nombreuses études visant à développer un logiciel de simulation permettant de prédire le comportement de la matière en condition de mise en œuvre.L'objectif de cette thèse est de s'intéresser plus particulièrement à la simulation de la phase de refroidissement. Pour cela, il est nécessaire de mettre au point un modèle décrivant la cinétique de cristallisation et pouvant tenir compte des contraintes liées aux conditions thermiques extrêmes dans lequel se déroule le procédé (température, présence d'oxygène, temps de cycle long), lesquelles peuvent avoir une influence sur la thermostabilité du polymère. Dans le cadre de cette étude, le choix s'est porté sur le Polylactide (PLA). Le PLA présente une faible stabilité thermique et une cinétique de cristallisation lente, ce qui facilite l'observation de ces deux phénomènes. Dans un premier temps, la thermodégradation du PLA a été étudiée et un modèle visant à décrire son évolution dans des conditions proches de celles du procédé, a été mis en place. Puis, une étude de cristallisation considérant l'influence de la masse moléculaire et du polymorphisme du PLA, a été réalisée afin de modéliser sa cinétique. Enfin, un couplage des deux modèles a été envisagé dans l'optique de les intégrer à une simulation globale des transferts thermiques impliqués dans le procédé de rotomoulage. / Rotational molding is a thermoplastic polymer processing technology which has been, for many years, suffering from a kind of empiricism.The simulation of rotational molding is believed to be the key to introduce new materials and more diversity in its applications. This work follows several studies aimed to develop a simulation software which would predict the material behavior in processing conditions.Consequently, this thesis will focus specifically on the simulation of the cooling phase. This type of simulation requires kinetic crystallization modeling, acknowledging the influence that the extreme thermal conditions of the rotomolding process can have on the thermal stability of the material. In this study we chose to work with Polylactic acid (PLA), a material suffering poor thermal stability and presenting with slow kinetic crystallization, making it suitable to observe these phenomenona. First, the thermal degradation of PLA has been studied and a model describing its behavior, under similar conditions to processing, has been proposed. Then, a crystallization study including the influence of the molecular weight, as well as the polymorphism of PLA, has been completed and the kinetic crystallization modeling has been performed. Finally, the integration of both models in a global simulation of the thermal transfers describing the rotomolding process has been investigated.
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The Self: Towards A Method for Queering Death : An Identity TestamentBerkert Wallard, Lisa January 2019 (has links)
“The Self: Towards A Method for Queering death” is an identity testament, a speculative method for designing the space of your own funeral before you die. It is a format to create a fair memorial of a person’s identity that does not feel welcome or fits in the current formats of burial ceremonies we have in Sweden today, usually connected to Christianity or other religious traditions. Even the secular burial traditions of Sweden today have a very clear traditional format and aesthetic that can be intimidating to a lot of members of society. “The Self” is also a method to relegate the power of narrative to whom it belongs. “The Self “is executed through this thesis, a sacred document, a spatial installation and a film, showing a possible scenario of a burial ceremony as a result of the method of the identity testament. This thesis demonstrates and problematizes the secular burial traditions in Sweden and how the common rituals are still based on the norms of Christianity, heteronormativity and traditional values, and why this is oppressing a lot of individuals in society. It does so by using a speculative method of an identity testament, which gives every human the right to own the narrative about their persona and who they were to the afterlife. It also problematizes the hierarchies and norms in society of what “family” means, and how consanguinity is valued by state and law. The term “queer” or “queering” is used in multiple ways, both as an adjective (being queer, a queer community, a queer sexual identity) but also as a verb or an adverb, as in the method used by the Queer Death Studies Network. The content of this thesis consists of texts, pictures, research in form of written sources and interviews, queer theory, descriptive design methods and descriptions of a sculptural exploration and spatial installation as well as a motion picture. The thesis asks and answers questions such as: How could a new type of burial ceremony - based on our secular beliefs in contemporary Sweden – look, feel and be arranged to be more connected to what we can relate as religion today? Is it possible to create an organized system to collect information about a person´s identity to be used as a formal ground to create a fair burial ceremony after the person’s death? The analysis focuses upon speculative ideas about what could happen if every person had a right to state a will for their intangible possessions and assets as well as their physical ones. The thesis also goes through multiple examples of cases of queer deaths where there have been strong needs to arrange an alternative funeral to feel safe and comfortable. Finally, the thesis reflects upon how this method could be used and if it really could be applied to society, and if so, who would be able to use it?
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Biker JacketEklöf, Andreas January 2013 (has links)
Staring to explore the fashionable biker jacket from the fifties lead to the discover that it hasn’t changed much since its origin. The stereotyped biker jacket with the genuine black leather and raw details is an impact model and thought the jacket no longer is worn while riding a bike is it still presenting an image of a rebellious life.The aim of this work is to explore our traditional view of the biker jacket through material and shape. Discovering that the bikers riding position has big similarities with a standing cow gave background to the material used in the classical jackets, the cow. A living animal, a material that once lived. To use the cows and the biker’s upper body as a model, recreating its shape into biker jacket’s to develop the shape of the biker jacket further. By experimenting with untraditional non-textile materials instead of using leather hopefully develop the traditional view of a jacket and bring alternative material and construction forward. Conclusion of the work is that when the materials with strong associations are mixed with the biker shape the materials take over and the definition of the biker jacket becomes more complex. New questions that has arise could be the use of other technical materials, what happens when giving the jacket other functions, is it still a biker jacket then. / Program: Modedesignutbildningen
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Crystallization of polyethylene terephthalate in injection moulding : experiments, modelling and numerical simulationVerhoyen, Olivier 01 February 1997 (has links)
Crystallization of polyethylene terephthalate in injection moulding : experiments, modelling and numerical simulation.
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Crystallization of polyethylene terephthalate in injection moulding : experiments, modelling and numerical simulationVerhoyen, Olivier 01 February 1997 (has links)
Crystallization of polyethylene terephthalate in injection moulding : experiments, modelling and numerical simulation.
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Structural changes during cellulose composite processingHalonen, Helena January 2012 (has links)
Two approaches for creating a new all-cellulose composite material have been studied: the biosynthesis of compartmentalised bacterial cellulose fibril aggregates and the compression moulding of commercial chemical wood pulps processed with only water. The objective was to study the structural changes during processing and the complexity of relating the mechanical properties of the final biocomposites to the nanoscale structure was highlighted. Solid-state CP/MAS 13C NMR spectroscopy was utilised to determine both the fibril aggregate width and the content of the different crystalline cellulose forms, cellulose I and cellulose II. Using this method, the quantities of hemicellulose present inside the fibre wall and localised at the fibre surfaces could be determined. The formation of cellulose fibrils was affected by the addition of hydroxyethylcellulose (HEC) to a culture medium of Acetobacter aceti, and the fibrils were coated with a thin layer of HEC, which resulted in loose bundles of fibril aggregates. The HEC coating, improved the fibril dispersion in the films and prevented fractures, resulting in a biocomposite with remarkable mechanical properties including improved strength (289 MPa), modulus (12.5 GPa) and toughness (6%). The effect of press temperature was studied during compression moulding of sulphite dissolving-grade pulps at 45 MPa. A higher press temperature yielded increases in the fibril aggregation, water resistance (measured as the water retention value) and Young’s modulus (12 GPa) in the final biocomposite. The high pressure was important for fibril aggregation, possibly including cellulose-cellulose fusion bonds, i.e., fibril aggregation in the fibre-fibre bond region. The optimal press temperature was found to be 170°C because cellulose undergoes thermal degradation at higher temperatures. The effect of hemicellulose was studied by comparing a softwood kraft paper-grade pulp with a softwood sulphite paper and a softwood sulphite dissolving-grade pulp. A significant fibril aggregation of the sulphite pulps suggested that the content and distribution of hemicellulose affected the fibril aggregation. In addition, the hemicellulose structure could influence the ability of the hemicellulose to co-aggregate with cellulose fibrils. Both sulphite pulp biocomposites exhibited Young’s moduli of approximately 12 GPa, whereas that of the kraft pulp was approximately half that value at 6 GPa. This result can be explained by a higher sensitivity to beating in the sulphite pulps. The effect of mercerisation, which introduces disordered cellulose, on the softwood sulphite dissolving-grade pulp was also studied under compression moulding at 170°C and 45 MPa. The mechanisms causing an incomplete transformation of cellulose I to II in a 12 wt% NaOH solution were discussed. The lower modulus of cellulose II and/or the higher quantity of disordered cellulose likely account for the decrease in Young’s modulus in the mercerised biocomposites (6.0 versus 3.9 GPa). / Två metoder för att skapa ett nytt kompositmaterial baserat på enbart cellulosa har studerats, biosyntes av fibrillaggregat bestående av bakteriecellulosa och varmpressning av kommersiella träfiberbaserade massor med vatten som den enda processkemikalien. Målet var att studera de strukturella förändringarna som sker under tillverkningsprocessen. Även komplexiteten i att relatera strukturen på nanonivå till de mekaniska egenskaperna hos de slutliga biokompositerna belystes. Med fastfas CP/MAS 13C NMR-spektroskopi var det möjligt att bestämma både fibrillaggregattjockleken och mängden av cellulosakristallformerna; cellulosa I och cellulosa II. Det var också möjligt att bestämma mängden hemicellulosa dels närvarande inuti fiberväggen och dels mängden lokaliserad på fiberytor. Tillsats av hydroxyetylcellulosa (HEC) i odlingsmediet för Acetobacter aceti påverkade bildandet av cellulosafibriller som blev belagda med ett tunt skikt av HEC, vilket också resulterade i löst bundna fibrillaggregat. HEC-beläggningen förbättrade fibrilldispersionen i filmerna och minskade sprickbildningen, vilket gav en biokomposit med mycket goda mekaniska egenskaper med kombinerad hög styrka (289 MPa), styvhet (12.5 GPa) och seghet (6%). Effekten av presstemperatur vid varmpressning (45 MPa tryck) studerades på sulfit dissolvingmassor. Högre presstemperatur gav ökad fibrillaggregering, ökat vattenmotstånd (mätt som vattenretentionsvärde) och högre styvhet (12 GPa) för biokompositen. Det höga trycket var också viktigt för fibrillaggregeringen, som troligen omfattar cellulosa-cellulosa samkristallisation dvs. fibrillaggregering i fiber-fiber-bindningsregionen. Den optimala presstemperaturen föreslogs vara 170° C pga. termisk nedbrytning av cellulosa vid högre temperaturer. Effekten av hemicellulosa studerades genom att jämföra sulfat pappersmassa med sulfit pappersmassa och sulfit dissolvingmassa. Mängden och fördelningen av hemicellulosa föreslogs ligga till grund för skillnaden i fibrillaggregering, som var mera uttalad i sulfitmassorna. Även hemicellulosans struktur kan påverka förmågan hos hemicellulosa att sam-aggregera med cellulosafibriller. Biokompositerna baserade på sulfitmassorna hade en styvhet på ca. 12 GPa, medan sulfatmassan bara hade hälften av den nivån ca. 6 GPa, vilket förklarades av sulfitmassornas högre känslighet för malning. Även effekten av mercerisering av sulfit dissolvingmassa varmpressad vid 170° C och 45 MPa studerades. Mercerisering introducerar oordnad cellulosa och mekanismerna som endast ger en partiell omvandling av cellulosa I till II i en 12 vikt% NaOH-lösning diskuterades. Den sämre styvheten hos den merceriserade biokompositen (6.0 resp. 3.9 GPa) förklaras troligen genom cellulosa II kristallens lägre styvhet och/eller den högre mängden av oordnad cellulosa. / <p>QC 20121106</p> / Wallenberg Wood Science Center / Biomime
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Investigation of Heat Conduction Through PMC Components Made Using Resin Transfer MouldingSakka, Aymen 16 November 2012 (has links)
The increasing demand for polymer matrix composites (PMCs) from the airframe industry raises the issues of productivity, cost and reproducibility of manufactured PMC components. Performance reproducibility is closely related to the manufacturing technique. Resin transfer moulding (RTM) offers the advantage of flexible manufacturing of net-shape PMC components with superior repeatability starting from ready-to-impregnate dry reinforcements. An RTM apparatus was developed for manufacturing PMC plates and demonstrator components representative of actual, PMC components and PMC moulds made and used in the airframe industry. The RTM process developed in this work involved making net-shape dry carbon fibre preforms and impregnating them an epoxy resin, targeting mould applications. Thermal repeatability of different net-shape PMC components manufactured using the RTM apparatus developed in-house was investigated. Effects of bonding an outer copper plate onto the PMC material, targeting mould applications known as integrally heated copper tooling (IHCT), were explored. Heat conduction through the PMC components was studied using simulation models validated by experimental data obtained primarily by thermography. Manufactured PMC components showed good repeatability, particularly in terms of thermal behaviour. The IHCT technique was found to be well suited for mould applications. Expected advantages of thermography were materialised. Finally, the simulation models developed were in good agreement with experimental data.
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