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Bedömning av tillverkningmetoder med MRLBaudin, Samuel, Fredriksson, Marcus January 2016 (has links)
Today´s industry is driven into development by an increasingly difficult situation of competition that gives less room for miscalculations in the production. One of the most important factors in maintaining your competitiveness is your ability to quickly and efficiently adopt new methods of manufacturing. With the help of new manufacturing methods, the company can improve product design, add new value creating features, and get a faster and more flexible production. However, problems arose with the grading of new manufacturing methods, in order to understand their matureness and if they are ready to be taken into production. This paper aims to investigate the possibility of a rating scale for manufacturing methods and then test this scale on a case study at Volvo CE, Eskilstuna, regarding their introduction of the method Power Skiving in their gear manufacturing. Through studying secondary data regarding already applicable methods for rating of the maturity of technologies and products that are to be introduced into production. Furthermore, have articles regarding proposed methods of rating the maturity of manufacturing methods been revised in order to get an insight into the current situation of rating manufacturing methods and to see what in specific could be of usefulness in rating manufacturing technologies. Beyond secondary data interviews have been conducted with the division of production development at Volvo CE Eskilstuna and with the Director Global Manufacturing Technology at Volvo CE. With the goal of gaining information regarding what they consider crucial in rating manufacturing methods and what is of importance in order to make this rating scale useful in the everyday work. Visits have been made in the production of slewing rings at Volvo CE in order to be able to gather data for the case study regarding the possible introduction of Power Skiving in Volvo CE´s gear manufacturing. The Authors have been able to construct certain criteria that aim to support todays rating matric of introduction of new products in order for it to also work for rating the readiness of new manufacturing methods. Today rating scales for manufacturing methods aren’t widely accepted, the authors, however, assume that it will gain acceptance and there will be more research regarding this subject. Further studies regarding documentation of the ratings and how this rating could be further integrated into daily operation at a company is recommended.
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Lung Injury and Repair: Early Therapeutic ConsiderationsRey Parra, Gloria Juliana Unknown Date
No description available.
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Simplified CFD modelling of tidal turbines for exploring arrays of devicesGebreslassie, Mulualem G. January 2012 (has links)
The status of marine current tidal energy technology is currently in the research and development phase, with a few deployments and tests of prototypes under-way in some countries. There is a huge pressure for tidal farms to be of Gigawatt scale in order to have a real, economically viable impact on renewable energy utilization targets outlined for 2020. A route to achieving this is the large scale energy farm philosophy, similar to wind farms, based on very large numbers of unit current tidal stream devices. However, this emerging technology development raises different research questions which lead to further problems in the practical implementation of tidal stream devices. Thus, the aim of this study was: (i) to develop a new, computationally cheap computational fluid dynamics (CFD) based model of the Momentum-Reversal-Lift (MRL) tidal turbine, and (ii) to perform a detailed calculations of the flow field of single and multiple turbines using the developed model to investigate the flow features such as, downstream wake structures, dynamics of the free surface, wake recovery, and the influence of wake interactions on the performance of individual devices. A new CFD based Immersed Body Force (IBF) model has been developed to represent the MRL turbine. The IBF model was developed based on the concept of actuator disc methodology by incorporating additional geometric features that induce energy absorption from the flow which also lead to a downstream wake structure intended to reflect more closely those of the real turbines than simple momentum sink zone models. This turbine model was thoroughly used to investigate the performance of the MRL turbine and the associated flow characteristics and proved its capability in analysing several issues relating to this design of tidal turbines. Several calculations have been carried out and a full range of operating points of the MRL turbine was formulated. A maximum power coefficient of, Cp = 0.665, was obtained with a blockage ratio of, B = 0.016. However, the performance of the turbine was improved at a higher blockage ratio both in a single and tidal stream farm investigations. The power coefficient of a single turbine was improved by about 3% when simulated with a blockage ratio of, B = 0.029, and even a higher value was obtained in a tidal stream farm containing three turbines configured in the spanwise direction which reached up to, CP = 0.761, with a global blockage ratio of, B = 0.027. These power coefficients are higher than the Lanchester-Betz limit of CP = 0.593 obtained at B = 0, which is mainly due to the tidal turbine operating in a constrained environment, high blockage ratio, that increases the thrust force on the device. The power coefficient of the IBF model showed consistently higher values compared to experiments and a detailed CFD model results. This indicates that the power coefficient calculated using the IBF model includes some other losses within the turbine region, such as losses due to viscous, shear etc. Investigations on the influence of closely packed clusters of turbines in a tidal streamfarm showed that a laterally close configuration of turbines improved the performance of individual turbines due to the blockage effect, which is created by the array of turbines in the span-wise direction. In contrast, a small longitudinal spacing between turbines inflicted a massive energy shadowing that affects the performance of downstream turbines. However, a tidal stream farm with a staggered turbine layout can reduce the longitudinal spacing by about 50% with a minimum of 6D lateral spacing compared with a regular turbine layout due to the advantage of using an accelerated bypass flows.
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HIV/Aids Relative Survival and Mean Residual Life AnalysisZhang, Xinjian 02 August 2008 (has links)
HIV/Aids Relative Survival and Mean Residual Life Analysis BY XINJIAN ZHANG Under the Direction of Gengsheng (Jeff) Qin and Ruiguang (Rick) Song ABSTRACT Generalized linear models with Poisson error were applied to investigate HIV/AIDS relative survival. Relative excess risk for death within 3 years after HIV/AIDS diagnosis was significantly higher for non-Hispanic blacks, American Indians and Hispanics compared with Whites. Excess hazard for death was also higher in men injection drug users compared with men who have sex with men (MSM). The relative excess hazard of old HIV/AIDS patients is significantly higher compared with younger patients. When CD4 increased, the relative excess hazard decreased; while with the increase of HIV viral load, the relative excess hazard decreased. This is the first study to use national wide data to examine the significance of HIV viral load as a determinant risk factor of disease progression after HIV infection; The mean residual lie needs to be further analyzed. INDEX WORDS: Human Immunodeficiency Virus (HIV), Acquired Immunodeficiency Syndrome (AIDS), Survival, Mean residual life (MRL).
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Autophagie comme cible thérapeutique potentielle pour le syndrome de Sjögren / Autophagy as a potential therapeutic target for Sjögren's syndromeLi, Baihui 13 September 2017 (has links)
Le syndrome de Sjögren (SS) est l'une des maladies autoimmunes (MAI) systémiques les plus fréquentes chez l’Homme. Cette maladie est caractérisée par une infiltration lymphocytaire dans les glandes exocrines conduisant à des symptômes dits de « yeux secs » et à la bouche sèche. Il n’existe actuellement aucun traitement curatif pour cette maladie. Le peptide P140 a été démontrée comme un outil thérapeutique efficace chez les patients atteints d'un lupus érythémateux disséminé (LED) et des souris modèles développant un lupus.L'autophagie est une voie intracellulaire conservée qui joue un rôle central dans le maintien de l'homéostasie cellulaire. En outre, l'autophagie a été démontrée comme un mécanisme de régulation de l'autoimmunité. Les effets bénéfiques du peptide P140 dans le lupus semblent étroitement liés à son effet d'inhibition de l’autophagie qui est hyper-activée dans le lupus. A ce jour, très peu de données sont connues concernant l'autophagie dans le SS. Le sujet de ma thèse porte i. sur l’étude et la compréhension des phénomènes de l’autophagie dans le SS et ii. sur l’effet éventuel du peptide P140 dans cette maladie.Dans cette étude, nous avons d’abord montré des effets protecteurs du P140 contre le SS dans les souris modèle MRL/lpr, comme en témoignent l’amélioration de l'inflammation, une diminution de l'infiltration lymphocytaire dans les SG de souris et une baisse des niveaux d'autoanticorps circulants. Nous avons également constaté que l'autophagie et les lysosomes étaient défectueux dans les SG des souris MRL/lpr et que le P140 rétabli le flux autophagique et l'acidité lysosomale. Ces résultats suggèrent que l'autophagie défectueuse et des défauts des lysosomes pourraient contribuer à la pathologie du SS et que les effets thérapeutiques de P140 pourraient être liés à son effet sur l'autophagie et les lysosomes.Les résultats obtenus dans le cadre de cette thèse nous offrent des informations décisives sur la pathogenèse de SS et suggèrent que l'autophagie pourrait être une cible thérapeutique de choix dans le SS. Au-delà, les effets protecteurs de P140 dans le modèle de souris SS nous éclairent sur l'application thérapeutique du P140 dans d'autres MAIs. / Sjögren's syndrome (SS) is one of the most common systemic autoimmune diseases (AIDs) in human. This disease is characterized by lymphocytic infiltration in the exocrine glands which leads to symptoms named dry eyes and dry mouth. There is no cure for SS currently. P140 peptide has been demonstrated to be an effective therapeutic tool in patients with systemic lupus erythematosus (SLE) and lupus mouse model. Autophagy is a conserved intracellular pathway that plays a central role in maintaining cellular homeostasis. In addition, autophagy has been demonstrated to be a mechanism of autoimmune regulation. The beneficial effects of P140 peptide in lupus seem to be closely related to its inhibitory effect on autophagy which is overactivated in lupus. However, the role of autophagy in SS is largely unknown. The aim of my thesis is: 1, to study the role of autophagy in SS and 2, to examine the possible effect of the P140 peptide in this disease. In this study, we first demonstrated the protective effects of P140 against SS in MRL/lpr mouse model, as evidenced by ameliorated inflammation, decreased lymphocyte infiltration in mouse salivary glands (SGs), as well as decreased levels of circulating autoantibodies. We also found that autophagy and lysosomes were defective in SGs of MRL/lpr mice and that P140 restored the autophagic flux and lysosomal acidity. These results suggest that defective autophagy and lysosome dysfunction may contribute to the pathology of SS and that the therapeutic effects of P140 may be related to its effect on autophagy and lysosomes. The results obtained in this study provide us valuable information about the pathogenesis of SS, and suggest that autophagy could be a potential therapeutic target in SS. Moreover, the protective effects of P140 in SS mouse model shed light on the therapeutic application of P140 in other AIDs.
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Τεκτονική δομή των αλπικών ενοτήτων στο φαράγγι του Κάμπου (ΒΔ Κρήτη)Δασκάλου, Μαγδαληνή 05 July 2012 (has links)
Η περιοχή μελέτης βρίσκεται στη ΒΔ Κρήτη στον Ν. Χανίων στο φαράγγι του Κάμπου. Το φαράγγι αυτό βρίσκεται δίπλα από το χωριό Κάμπος από όπου πήρε και το όνομα του. Σκοπός της εργασίας αυτής είναι να μελετηθούν οι τεκτονικές δομές των αλπικών ενοτήτων στο φαράγγι του Κάμπου. Η μελέτη χωρίζεται σε δύο ενότητες, την τεκτονική ανάλυση των στοιχείων υπαίθρου και την μικροτεκτονική ανάλυση. Η τεκτονική ανάλυση βασίζεται σε μεσοσκοπικές παρατηρήσεις που συνοδεύτηκαν από μετρήσεις με πυξίδα τύπου Clar στην ύπαιθρο. Στην εργασία παρουσιάζεται γεωλογικός χάρτης της περιοχής με όλες τις λιθολογικές ενότητες και τις τεκτονικές δομές της περιοχής, γεωλογικές τομές της καθώς και προβολές των μετρήσεων σε δίκτυα Schmidt. Η μικροτεκτονική ανάλυση έγινε σε λεπτές τομές στο μικροσκόπιο από πετρώματα της περιοχής μελέτης. Από τις τομές αυτές τραβήχτηκαν φωτογραφίες κρυστάλλων που χρησιμοποιήθηκαν για τον προσδιορισμό του ποσού της παραμόρφωσης. / Description of the tectonic units in Kampos area in NW Crete in the mesoscopic file as well as in the microscopic field using slides in the microscope from the studying area.
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Abordagem MRL, Arima e Data Mining para otimização de custos no suprimento energético em plantas petroquímicasSantana, Delano Mendes de January 2018 (has links)
Orientador: Prof. Dr. Douglas Alves Cassiano / Coorientador: Prof. Dr. Sérgio Ricardo Lourenço / Tese (doutorado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, Santo André, 2018. / Uma forma de otimização dos recursos energéticos de uma planta petroquímica é a
utilização de Mix Integer Linear Programing (MILP) para decisão da configuração
ótima do acionamento dos equipamentos da unidade. Entretanto uma questão ainda
em aberto é qual a correlação existente entre a série temporal destes ganhos
energéticos com o preço da energia no mercado livre, a temperatura ambiente, a carga
da planta e a demanda elétrica desta planta petroquímica. Dessa forma, o objetivo
deste trabalho foi obter a correlação entre estas variáveis. A metodologia utilizada
contou com três abordagens de exploração de correlações, a primeira foi a
Modelagem de Regressão Linear (MRL), a segunda a Autoregressive Integrated
Moving Average (ARIMA) e, a terceira, a Data Mining. Como principais resultados
foram obtidas as correlações entre estas variáveis pelas três abordagens, além da
comparação das regressões em termos de: qualidade de ajuste do modelo;
visualização dos dados e aplicação em aplicativos comuns como o Excel®.
Adicionalmente foram descobertos padrões escondidos nos dados e gerou-se
conhecimento acadêmico capaz de suportar decisões industriais que conduzam a
melhorias de eficiência energética. / Is possible to optimize the energy resources of a petrochemical plant using Mix Integer
Linear Programing (MILP) to decide the optimal configuration of the equipment.
However, a still open question is what correlation exists between the time series of
these energy savings with the price of energy in the free market, the ambient
temperature, the plant load and the electric demand of this petrochemical plant. The
objective of this study is to obtain the correlation between these variables. Three
approaches was used, Linear Regression Modeling (LRM), Autoregressive Integrated
Moving Average (ARIMA) and Data Mining. Were obtained the correlations between
these variables by the three approaches, besides the comparison of the regressions
in terms of: adherence to the real values; data visualization and application in common
applications like Excel®. In addition, hidden patterns were discovered in the data and
academic knowledge was generated, supporting industrial decisions that lead to
improvements in energy efficiency.
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Le tissu adipeux : tissu modèle pour étudier le lien entre organisation et fonction ainsi que la régénération tissulaire / Adipose tissue : model to study the link between organization and function as well as tissular regenerationLabit, Elodie 09 September 2016 (has links)
Le tissu adipeux (TA) est connu pour sa plasticité puisqu'il est capable de s'hypertrophier ou de s'atrophier, en fonction de la situation métabolique de l'individu. Cette plasticité est liée au fait que le TA joue un double rôle dans le maintien de la balance énergétique : il est à la fois i) réserve d'énergie mobilisable (adipocytes blancs) mais également ii) consommateur d'énergie via la thermogénèse (adipocytes bruns, adipocytes beiges). En raison de l'évolution croissante des maladies métaboliques dites de surcharge dans lesquelles ce TA va s'hypertrophier, la majorité des études abordent cette notion de plasticité à l'échelle cellulaire, et se focalise ainsi sur les adipocytes (prolifération, différenciation, activité) et les autres populations cellulaires résidant dans le TA, capables d'interagir avec eux. En revanche, il y a très peu d'études sur cette plasticité à l'échelle tissulaire. Au cours de ma thèse, je me suis intéressée i) à l'organisation tissulaire d'un dépôt de TA blanc (dépôt sous-cutané inguinal) et ii) les conséquences d'une ablation massive du TA blanc. L'ensemble de ce travail a été réalisé chez la souris.A l'aide de l'imagerie 3D sur tissu entier, nous montrons que ce dépôt est hétérogène : il est composé d'une partie dans laquelle il est possible de segmenter des entités fonctionnelles (lobules ?), située au cœur du dépôt, et d'une partie non segmentable, située à la périphérie du dépôt. Cette hétérogénéité structurale est associée à une hétérogénéité fonctionnelle : les deux régions se distinguent en termes de morphologie adipocytaire et de pattern d'expression génique. De plus, seule la partie segmentable répond à la mise au froid des animaux par une up-régulation du niveau d'expression d'Ucp1 et d'autres gènes marqueurs du " brunissement ". Parallèlement à cela, nous montrons que selon la souche de souris (C57bl6 et MRL), la réponse du TA inguinal à une ablation partielle n'est pas la même : chez la souris MRL (rare mammifère capable de régénération), ce dépôt adipeux est capable de régénérer, ce qui n'est pas le cas chez la souris C57Bl/6. La régénération est inhibée chez la souris MRL par un traitement avec un agoniste des récepteurs aux opioïdes (tramadol) alors qu'elle peut être induite chez la souris C57Bl/6 par un antagoniste de ces récepteurs (naloxone). Cette régénération est dépendante d'une forte et intense production d'espèces actives de l'oxygène par les granulocytes. L'utilisation de souris invalidées pour le récepteur mu démontre l'implication de cette sous-famille de récepteurs. Enfin, cet effet des opioïdes est majoritairement le fait des cellules immunitaires, et plus particulièrement les granulocytes. Ces données mettent en exergue une nouvelle vision du TA blanc sous - cutané, qui ne doit pas être considéré comme un tissu inerte mais bel et bien comme un tissu hétérogène complexe (structurellement et fonctionnellement) pouvant être capable de régénération. / Adipose tissue (AT) is very plastic tissue. During metabolic disease, it would be overdeveloped or atrophy. It is due to the fact that AT is i) energy storage thanks to white adipocyte and ii) energy consumer thanks to brown or brite adipocyte. The cellular composition is very well studied (adipocytes activity, proliferation, differenciation, link between AT stromal cells / adipocytes) but the tissue organization of AT is not known. During my thesis work, we study the i) tissular organization of white AT and ii) AT response after massive removal of white AT. Mice are used for this work. In the first step, our 3 dimensional imaging of white AT shows that AT is heterogeneous tissue: AT has 2 components: segmentable area, in the AT core and non-segmentable area, in the AT periphery. This structural heterogeneity is correlated with functional heterogeneity because segementable area differs to non-segmentable area from adipocyte shape and pattern genic expression. Furthermore, only segmentable area can be respond to cold exposure by Ucp1 up-regulation and browning genes markers. In the second step, massive ablation of subcutaneous white AT is performed on two mice strains: C57Bl/6 and MRL (known to be able to regenerate). MRL mice inguinal AT regenerate, unlike inguinal AT of C57Bl/6 mice. The use of antagonist of opioid receptor (naloxone) treatment leads regeneration AT in C57Bl/6. In opposite, opioid receptor agonist (tramadol) treatment in MRL mice inhibits AT regeneration. AT regeneration is dependant of burst oxydatif production by granulocytes. The use of the receptor knock down mice highlights that is the only receptor is involved in AT regeneration. More precisely, opioids effects are mediated by receptor on granulocyte immune cells.
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Identifying and Evaluating Novel Biological Targets to Improve Musculoskeletal Tissue Engineering StrategiesLalley, Andrea L. January 2014 (has links)
No description available.
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Hydrodynamic analysis of the momentum-reversal and lift tidal turbineBerry, Matthew James January 2017 (has links)
Tidal energy has the potential to make a valuable contribution to meeting future global energy demands. Converting the energy of tidal streams into useful electricity can be achieved with use of tidal-stream turbines, such as the Momentum-Reversal and Lift (MRL) device. This turbine utilises a blade motion where each blade rotates continuously through 180° about its own axis for every 360° of turbine rotation. The aim of the design is to harness both useful lift and drag forces when rotating at relatively slow speeds. However, no detailed analysis of the time-varying fluid dynamic behaviour of the turbine has been undertaken before this study. The primary aim of this study has been to further understanding of the performance characteristics of the MRL turbine design, focusing on a laboratory- scale device. The study has analysed both the time-averaged and time-varying torque and power output, and the associated fluid-dynamic structure of flow through the turbine. A secondary aim was to generate data that can be used by other researchers who focus on the wake generation of the MRL tidal turbine. This study has used OpenFOAM to develop a time-dependent RANS CFD model and investigate the performance of the MRL turbine. To allow validation of the CFD model, experiments were firstly undertaken in order to measure the cycle-mean torque and power output of the turbine when operating in a laboratory flume. Measurements of the flow velocity at a number of upstream and downstream locations were also taken, in order to allow comparison with the CFD simulation results, where appropriate. Also, in order to allow validation of the CFD approach against time-varying data, the motion of the turbine blades was analysed. This allowed suitable experimental test cases to be identified from the literature and CFD simulation results have been compared to these. A detailed sensitivity analysis of the MRL turbine CFD model was carried out, followed by two-dimensional simulations of the turbine involving a single-blade and three-blades. Three-dimensional simulations were also undertaken, with results compared to the gathered experimental results. Finally, the effect of varying turbine solidity was investigated with the CFD model. Overall it was found that the CFD simulations successfully reproduce the rotational speed at which maximum torque and power are developed. However, the three-dimensional simulations significantly over-predict the magnitude of results in comparison to the gathered experimental results. Regardless, the two- and three-dimensional simulations have allowed detailed analysis of the flow behaviour and structures that are responsible for the development of blade forces and turbine torque.
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