Thèses sur le sujet « Slti »

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Since 2008, the Normative SLTI n?? 04 (IN4) has been established as the legal instrument for planning and supporting the procurement process of Information Technology (IT) solutions. Risk Management, which is a mandatory phase in IN4, seeks to ensure that the inherent risks in this process are mitigated. However, recent surveys from supervisory and control agencies have indicated a low maturity in this practice. This work collected the perception of managers involved in IT procurement regarding the compliance to the procurement risk management process according to the Supplementary Normative DSIC n?? 04 (NC4). For this purpose, an online survey was conducted through a questionnaire containing 33 questions, which were answered by 35 managers of 15 organizations. Completed this phase, the analysis of the results was made and 93% of respondents reported adhering to IN4, however, the survey findings contradicts this high rate, considering the results of specific assessments for each phase of risk management that did not exceeded 59% of compliance in IN4, and the phase where the estimation of the probability of risks should occur had the lowest compliance rate, only 22%. However, the main finding of this research took place in the stage that evaluated the adoption of NC4 guidelines, where only 15% of managers reported adopting it fully. These findings points out to the possible ignorance of the risks that the IT procurement process is exposed as well as the possible occurrence of frauds and the waste of public resources which, ultimately, may represent inefficiency in achieving expected results as well as possible losses to society.
Desde 2008, a Instru????o Normativa n?? 04/SLTI (IN4) vem se consolidando como um instrumento legal de planejamento e apoio ao processo de contrata????o de Solu????es de Tecnologia da Informa????o (TI). A Gest??o de Riscos, etapa obrigat??ria da IN4, busca assegurar que os riscos inerentes a este processo sejam mitigados. Entretanto, recentes levantamentos de ??rg??os de fiscaliza????o e controle apontam baixa maturidade nesta pr??tica. Este trabalho fez uma an??lise da percep????o de gestores envolvidos em contrata????es de TI quanto ?? conformidade ao processo de Gest??o de Riscos da IN4 e quanto ao conhecimento e ado????o da Norma Complementar n?? 04/DSIC (NC4). Para tanto, foi realizado um levantamento on-line em que 35 gestores de 15 ??rg??os responderam a 33 quest??es. Conclu??da esta etapa e feita a an??lise dos resultados, 93% dos respondentes informaram conformidade ?? IN4, entretanto, os achados do levantamento se opuseram a este elevado ??ndice, tendo em vista que os resultados das avalia????es espec??ficas para cada etapa da gest??o de riscos na IN4 n??o superaram os 59% de conformidade, sendo a estimativa da probabilidade de ocorr??ncia dos riscos a etapa que apresentou o menor ??ndice de conformidade, 22% apenas. Contudo, o principal achado desta pesquisa se deu na etapa que avaliou a ado????o das diretrizes da NC4, onde apenas 15% dos gestores informaram adot??-las integralmente. Estas descobertas podem sinalizar o poss??vel desconhecimento dos riscos que um processo de contrata????o de TI est?? exposto e a poss??vel ocorr??ncia de ilegalidade e desperd??cio de recursos p??blicos que, em ??ltima an??lise, podem representar inefici??ncia no alcance dos resultados e preju??zos para a sociedade.

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2014.
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As organizações públicas buscam cada vez mais que os seus Processos de Contratação de Tecnologia da Informação sejam bem elaborados e aperfeiçoados para que se adequarem às leis, normas e regulamentações, em sua maioria, reunidas na IN04/SLTI. Este trabalho apresenta uma proposta de avaliação de maturidade para o Processo de Contratação de TI da Secretaria de Logística de Tecnologia da Informação (SLTI), tendo como estudo de caso o Instituto Nacional do Seguro Social (INSS). A avaliação da maturidade dos processos com foco na gestão de riscos fornece informações podem apoiar a organização a planejar, executar e monitorar suas atividades visando à obtenção dos seus objetivos e melhoria contínua. Para se chegar à proposta de avaliação de maturidade recorreu-se ao conceito da Janela de Johari, melhores práticas de modelos já consolidados como Risk Maturity Model (RMM), Capability Maturity Model Integration for Acquisition (CMMI-ACQ) e Control Objectives for Information and Related Technology (COBIT). ______________________________________________________________________________ ABSTRACT
Public organizations increasingly seek that tlıeir Information Technologv Aoquisition Processes are well developed and enhanced iıı such a wav tlıat are adherent to laws. rules and regulations. mostlv gathered in the IN 04 / SLTI. This work proposes a matu rity assessment for tlıe Acquisition Processes of the Logistics and Information Technology Information Technology Secretary (SLTI), taking the National Social Security Institute (INSS) as a case study. Assessing the maturity of processes with a focııs on risk man agernent provides information to support the organization to plan, execute and monitor their activities aimed at achieving its goals and continous improvement.. To reach the proposed maturity assessment we ıısed tlıe concept of the Johari Window, best practices models already established as Risk Maturity Model (RMM). Capability Maturity Model Integration for Acquisition (CMMI-ACQ) and Control Objectives for Information and Related Technology (COBIT).

Suicide in rural areas has not received significant attention in the research literature to this point, although suicide rates are higher among adults and older adults in rural areas than in urban areas. The aims of the study were as follows: (1) establish the feasibility of assessing suicide ideation and history of suicidal behavior; (2) determine preliminary estimates of the prevalence of suicide ideation, and history of suicide attempts; and (3) examine the effectiveness and acceptability of safety and referral plans for individuals whose responses indicated elevated suicide risk, in rural communities with limited access to referral care. Participants were 96 adults aged 40 to 85 years old (M = 57.34, SD = 11.47) residing in West Texas. Our results indicate that 26% of participants endorsed a lifetime history of suicide ideation and/or suicide attempt(s) and 12.5% reported suicide ideation in the past year. In addition, 93.4% of participants reported that participation in our suicide-focused study was an excellent or good experience. Results suggest that individuals in rural communities are willing to talk about suicide, found the experience helpful, and were satisfied with the referral process.

The present work is concerned with the investigation of the slit die extrusion of molten polymers, and a systematic strategy is developed for the modelling of its major aspects. The objective is to provide a fundamental understanding of the flow phenomena within such a die, coupled with thermal and mechanical interaction of melt and die body, and to provide user friendly software for analysis and design. Isothermal, non-Newtonian flow in the large aspect ratio channels of such dies is modelled using a Hele-Shaw formulation. The pressure field in the die causes a change of the flow channel dimensions, and hence alters the melt distribution. An experimental technique is applied to determine this die body deflection in a 1.3m commercial die; it is found to be substantial. Modelling of the die deformation using a commercial 3-D finite element package is described, with the load being based on a pressure field previously determined in the undeflected flow channel geometry. Prompted by unsatisfactory results, an algorithm is developed to evaluate the die body deflection iteratively, by coupling a 2-D thick plate analysis with the Hele-Shaw flow analysis, resulting in significantly improved results. Modelling of the conjugate melt flow/die heat transfer problem on the die cross-section is also carried out. Viscous heat generation, conduction and convection energy transport in the melt coupled with heat conduction in the die body are considered, together with the influence of electrical die heating and heat losses from the die surfaces by convection and radiation. Conclusions are drawn on thermal aspects of die design and operation. A graphical user interface embedded in Microsoft Windows is developed for a number of finite element codes, facilitating their use by non-specialists, and providing graphical displays of results. An outline of the operation of the complete package is described, including a convenient contouring algorithm.

Fastighetsmäklare har ett rykte att de tjänar mycket pengar utan att anstränga sig. Stämmer detta eller är det bara en bild som media skapat? Med den bakgrunden valde vi att titta närmare på vilka lönesystem för fastighetsmäklare som finns i branschen. Med avgränsning till privatbostadsmarknaden och Stockholm-Uppsala regionen.

Syftet är att öka kunskapen om olika lönesystem för fastighetsmäklare på privatbostadsmarknaden.

Vi har även tittat på hur det fungerar med sjukpenning, föräldrapenning och a-kassa. Sedan har vi valt att titta på hur en mer traditionell lön ser ut och vilka förmåner utöver lön som kan förekomma.

Vi har genomfört två intervjuer angående hur en traditionell eller ”normal” lön fungerar samt fyra intervjuer med fastighetsmäklare angående lönesystem för fastighetsmäklare.

Real estate agents have a reputation of making a lot of money without any effort. Is this true or is it just a picture painted by the media? With this in mind we have decided to take a closer look at different systems for how real estate agents get their salary. We have decided to narrow our thesis down to real estate agents who are operating in the Uppsala-Stockholm region with residential sales.

The purpose of this thesis is to increase the knowledge about different systems for salaries for real estate agents who are working with residential sales.

What happens if you get sick, if you become a parent or if you loose your employment are questions that we discuss.

We have interviewed real estate agents and asked them about their terms for salary. We have also looked at how a more traditional salary works.

LDSS-2 is a low dispersion survey spectrograph for the William Herschel Telescope. It was constructed to meet an increasing demand for large scale statistical surveys of stellar and galactic populations. This thesis describes its design, construction and installation, together with additional research concerning the fabrication of multi-slit aperture masks.LDSS-2 has a similar optical system to its predecessor LDSS-1, but it can hold greater numbers of aperture masks, filters and grisms, and its control system is fully automated. This is expected to improve its observing efficiency and allow LDSS-2 to be run as a common-user instrument. A range of instrument characterisation tests were performed, and they confirmed that LDSS-2 is capable of meeting its astronomical objectives. Its peak efficiency with the medium-blue grism was found to be 20.4% at 5915A with half-power points at 4135A and 7225A.Six different types of aperture mask were investigated, of which two (photochemically etched and mechanically milled) were tested using LDSS- 2. Work was begun towards the development of laser-cut masks, including the procurement of a 16W carbon dioxide laser and a motorised X-Y table. At present, mechanically milled masks offer the best compromise between cost, lead time, flexibility and quality for an instrument such as LDSS-2. Movable-slit masks may be preferred if access to the focal plane is restricted, but at present they are limited to lower multiplex gains. Laser-cut masks appear to offer the most potential for development in the immediate future, but liquid crystal masks may also become competitive in the longer term.

In recent years extremely small satellites have been developed in response to trends in the space industry to achieve more for less cost. Extremely lightweight and efficiently packaged deployable structures are essential for achieving large-scale applications including communication antennas, solar arrays, and in recent years, deorbiting drag-sails. This thesis is motivated for developing novel deployable helical antennas for space-based maritime surveillance. The helical antenna technology provides packaging efficiency and radio frequency characteristics superior to the latest efforts of international research groups. To achieve this, the research presented focuses on developing the proven bistable composite slit tube (BCST) deployable technology. These are open-section tubular structures which can be deployed and rolled up into a compact coil, analogous to a tape measure, but do not require constraint to remain stowed. This behaviour is referred to as bistability and enables lightweight and relatively simple deployable structures for spacecraft applications. New forms of BCST are modelled through the introduction of additional curvatures, manufactured and described in this work with two new subcategorisations established: toroidal and helical. Toroidal BCSTs are doubly curved with both principal curvatures initially non-zero in the deployed stress-free state. Helical BCSTs are doubly curved and twisted out-of-plane. Investigations into the effects of geometrical parameters and laminated composite material properties on the bistable coils of both types are presented. The results provide an understanding of bistable behaviour in new forms of BCST previously neglected in the literature, which is almost exclusively focused on straight forms. As a consequence of this research, new deployable structure technologies are envisaged in the areas of compact terrestrial shelters and small satellite communications.

Abstract: Oil pollution and spills cause serious damage to marine ecosystems and coastal environments. Currently, oily waters recuperated form a spill must be shipped onshore for treatment. This limits the volume of water that can be treated during a spill. There is a need to develop technologies to treat oily waters below 15 ppm (parts per million) at the site of the spill. Synthetic membrane technologies are widely used in water treatment and purification. They can offer an on-site solution to contaminated oily water treatment in oil production and spills. The suitability of a membrane for use in this application is determined by the type of material used in its fabrication. Compared to polymeric membranes, inorganic membranes are inert to microbiological degradation, offer high chemical and thermal resistance, and can easily be backflushed and cleaned once fouled. However, inorganic membranes consisting of metal oxides are heavier and more expensive than polymeric membranes, due to their bulky and brittle ceramic support layers. This limits their application when the overall weight of a process unit is of concern. A newly developed 2D/3D material, named twinned alumina nanosheets (TAN), has recently been used to make dynamic membranes. The nanoplatelets forming TAN have a length of 4 µm, a width of 1 µm, and a thickness of 100 nm. They have a very high permeability, a 0.2 µm-pore size and a porosity up to 88% due to their low nanosheet volume. These unique characteristics make TAN a very promising material to form membrane selective layers. However, they must be supported on a very open layer in order to take advantage of their high porosity. In this work, a composite membrane was produced with a selective layer of 2D/3D alumina nanoplatelets deposited onto stainless steel meshes and ceramic supports. The structure of the TAN in the selective layer was reinforced with binders. The main objective of this work was to verify the adhesion of the TANs onto the support. The crystallization of TAN was optimized to obtain an open 2D/3D structure. This structure was then deposited on a stainless-steel mesh. The mesh was pretreated by electrochemical etching to achieve a re-entrant surface. The mesh was immersed in an etching solution and placed parallel to a conductive graphite plate under a constant electric potential of 5V for 4 min. Aqueous solutions of silica sol and colloidal silver were tested as binding agents. They were deposited on the mesh with TAN and sintered for 4 hrs. Experiments were performed on testing stainless steel meshes with different opening sizes and comparing different calcination temperatures. The best sintering temperature was 800°C for a mesh with an opening size of 35µm. The synthesized membrane was challenged with a suspension of 10 ppm bentonite clay at a constant pressure of 100 mbar. The integral structure of a TAN membrane produced with a 2.5wt% silica binder was maintained after backflushing. The 2.5wt% silica membrane had a high flux and the particle filtration process for this membrane was modelled as pore constriction and intermediate blocking, indicating that backflushing provided the deep cleaning of pores. According to the SEM images, the 2.5wt% silica membrane preserved the integral structure of the TAN, while the pores tended to fill with silica at higher silica concentrations. The effective pore size of the 2.5wt% silica membrane was estimated to be the smallest, which is approximately 0.53 μm. The 7.5wt% silica membrane had half the permeate flux of the other membranes, because of the high concentration of binder filling the pores of the TAN selective layer. The SiO 2 binder had a positive effect in reinforcing the TAN particles. The flux of the membrane did not increase after backflushing indicating that the selective layer of the membrane was securely bound to the stainless steel mesh. The membrane exhibited flux decline between backflushings indicating that particles were retained on its surface. SEM images taken after the filtration showed that this membrane completely released bentonite particles form its pores. Tests were also performed with a membrane having two TAN coatings on the wire mesh. This reduced the flux but did not improve the retention of fine particles. Colloidal silver was found to be a poor binding agent as particles were released particles from its selective layer. Silica was a highly successful binding agent while colloidal silver was not. TAN was also successfully deposited onto ceramic supports. It was also retained on top of the membrane after backflushing. The results of this work demonstrate that TANs reinforced and bound with silica are a promising type of material to form membrane selective layers. These layers have an open pore structure with a three-dimensional channel connectivity on both stainless steel and ceramic supports. The selective layer was successfully bound to the stainless steel supports. If the pore size of this membrane were to be reduced, it would meet the requirements for use at the site of an oil spill to treat contaminated waters as it does not need the heavier supports found in traditional ceramic membranes. Résumé: La pollution et les déversements d'hydrocarbures causent de graves dommages aux écosystèmes marins et aux environnements côtiers. À l'heure actuelle, les eaux huileuses récupérées d'un déversement doivent être expédiées à terre pour leur décontamination. Ceci limite le volume d’eau contaminé qui peut être traité. Il est nécessaire de développer des technologies permettant de traiter les eaux huileuses en dessous de 15 ppm (parties par million) sur le site du déversement. Les technologies membranaires sont largement utilisées dans le traitement et la purification de l'eau. La possibilité de se servir d’une membrane dans cette application est déterminée par les matériaux utilisés dans sa fabrication. Comparées aux membranes polymères, les membranes inorganiques sont inertes vis-à-vis de la dégradation microbiologique, offrent une résistance chimique et thermique élevée et peuvent facilement être rincées et nettoyées une fois encrassées. Cependant, les membranes inorganiques constituées d'oxydes métalliques sont plus lourdes et plus coûteuses que les membranes polymères, en raison de leurs couches de support en céramique volumineuses et cassantes. Cela limite leur application lorsque le poids total d'une unité de traitement est préoccupant. Un matériau 2D/3D récemment développé, appelé TAN (Twinned Alumina Nanosheets), a récemment été utilisé dans la formation de membranes dynamiques. Les nano-plaquettes formant les TAN ont une longueur de 4 µm, une largeur de 1 µm et une épaisseur de 100 nm. Ils ont une très haute perméabilité, une taille de pores de 0,2 µm et une porosité allant jusqu'à 88% en raison du faible volume des nanofeuilles. Ces caractéristiques uniques font du TAN un matériau très prometteur pour la formation de couches sélectives de membranes. Cependant, ils doivent être déposes sur une couche très ouverte afin de tirer parti de leur grande porosité. Au cours de ce travail, une membrane composite a été réalisée avec une couche sélective de nanoplaques d’alumine 2D / 3D (TAN) déposées sur deux types de supports; des mailles en acier inoxydable et des supports en céramique. La structure du TAN dans la couche sélective a été renforcée avec des liants. L'objectif principal de ce travail était de vérifier l'adhérence des TAN sur le support. La cristallisation des TAN a été optimisée pour obtenir une structure 2D/3D ouverte. Cette structure a ensuite été déposée sur un treillis en acier inoxydable. Les mailles ont été prétraitées pour obtenir une surface réentrante. Le maillage a été immergé dans une solution de gravure et placé parallèlement à une plaque de graphite conductrice sous un potentiel électrique constant de 5 V pendant 4 min. Des solutions aqueuses de sol de silice et d’argent colloïdal ont été testées en tant que liants. Ils ont été déposés sur la maille et frittés pendant 4 heures. Des expériences ont été effectuées sur des mailles en acier inoxydable avec différentes tailles d’ouverture et températures de calcination. La meilleure température de frittage était de 800 ° C pour un treillis ayant une taille d'ouverture de 35 µm. La membrane synthétisée a été mise à l’essai avec une suspension de 10 ppm d'argile bentonite à une pression constante de 100 mbar. La structure intégrale de la membrane couche de TAN produite avec un liant à 2,5wt% de silice a été maintenue après les tests de perméabilité. La structure 3D poreuse a tendance à se remplir de silice à des concentrations de silice supérieures à 2,5wt%. La taille effective des pores de la membrane produite avec 2,5wt% de liant de silice a été estimée à 0,53 µm. Le flux de la membrane n'a pas augmenté après le rinçage, indiquant que la couche sélective de la membrane était liée de manière sûre au maillage en acier inoxydable. La membrane présentait un déclin de flux entre les rinçages indiquant que des particules étaient retenues à sa surface. Les images au microscope à balayage prises après la filtration ont montré que cette membrane libère complètement les particules de bentonite de ses pores. Des essais ont également été réalisés avec une membrane comportant deux revêtements TAN sur le treillis métallique. Cela réduit le flux mais n'améliore pas la rétention des particules fines. L'argent colloïdal s'est avéré être un agent de liaison médiocre car des particules sont libérées de sa couche sélective. La silice était un liant très efficace, contrairement à l'argent colloïdal. Le TAN a également été déposé avec succès sur des supports en céramique. Il est également resté sur la membrane après le rinçage à contre-courant. Les résultats de ce travail démontrent que les TAN renforcés avec un liant de silice sont un type de matériau prometteur pour former des couches sélectives, avec des structures à pores ouverts possédant une connectivité de canal tridimensionnelle, sur des supports en acier inoxydable et en céramique. La couche sélective a été liée avec succès au support en acier inoxydable. Si la taille des pores de cette membrane devait être réduite, elle pourrait être utilisée sur le site d'un déversement d'hydrocarbures pour traiter les eaux contaminées car elle ne nécessite pas les supports plus lourds que l'on trouve dans les membranes de céramique traditionnelles.

Slits are large secreted proteins which mediate their functions by binding to single pass transmembrane receptors called Robo. This signalling axis was first identified as a pivotal guidance mechanism in the development of the nervous system. A repulsive activity of Slit proteins controls the projection and movement of Robo expressing neurons in Drosophila and vertebrates. Slit and Robo expression is not limited to the nervous system or development only, they were found to be expressed in many different tissues both in embryo and adult organism. Correspondingly, the Slit-Robo signalling axis now is implicated in many other biological and pathological processes such as angiogenesis, cancer and tissue remodelling. This study sought to investigate two different aspects of the Slit-Robo signalling system: Robo1 transmembrane signalling mechanism and possible Slit-Robo roles within the immune system. Robos and other type I transmembrane receptors are unable to transmit signal across the membrane within a single molecule because a single transmembrane α-helix restricts propagation of conformational changes between extracellular and intracellular parts of the protein. Therefore, the type I receptors usually act as homo- or heterooligomers, formation or dissociation of which is controlled by ligand binding. Based on indirect evidence a similar transmembrane signalling mechanism was suggested for Robo receptors. It was hypothesized that Slit binding induces changes in oligomeric state of Robo which in turn initiates downstream signalling events. In order to test this hypothesis and determine details of the transmembrane signalling mechanism, the oligomeric state of Robo1 receptor was assessed in live cells using two different fluorescence resonance energy transfer (FRET) based methods. A strong FRET signal was observed between differently tagged Robo1 proteins, indicating that the receptor forms oligomers in the resting state. However, contrary to the initial hypothesis, the addition of Slit2 protein did not have an observable effect on the FRET signal and thus on receptor oligomeric state. Moreover, Robo1 proteins were found to form higher density domains within the cell membrane. This property could be abolished by removing the intracellular part of the protein indicating constant Robo1 association with intracellular structures. These data show that the Robo1 transmembrane signalling mechanism might be more complicated than initially expected and likely involves structural changes within the Robo1 oligomer or Robo1 complexes with other proteins. The Slit-Robo signalling axis was linked to the immune system when it was demonstrated that Slit2 is able to inhibit chemotactic leukocyte migration and reduce inflammatory responses in mice. However, the precise role of these proteins remained unknown. In order to gain further insight into possible Slit-Robo functions within the immune system promoter analysis was performed with the aim to identify transcription factors responsible for the control of these proteins. Among many putative transcription factors discovered, Foxn1 was the most prominent as its binding site was identified both in Slit2 and Slit3 promoters. Development and functions of thymus, a primary lymphoid organ responsible for T cell development, is regulated by Foxn1 and since thymic activity includes active and abundant leukocyte movement into, out-of and within the organ, a hypothesis was suggested that Slits contribute to regulation of these processes. Quantitative Slit2-Slit3 expression studies and assessment of embryonic thymus cellular composition in Slit2 knockout mouse were employed to test this hypothesis. Quantitative PCR revealed that both Slit2 and Slit3 are downregulated four-fold in thymic epithelial cells starting embryonic stage E13, however no differences in cellular composition of embryonic thymi were detected between wild type and Slit2 knockout animals using flow cytometry. Possible Slit2 and Slit3 redundancy might be the reason for the lack of observable effects, unfortunately a Slit3 knockout model was unavailable for these studies. Interestingly, flow cytometry also revealed that in addition to thymic epithelial cells, Slit2 is expressed by pericyte type cells surrounding the thymic vasculature. It seems that Slit proteins have intricate and regulated expression patterns within the thymus, however their precise role remains an open question. In summary, data collected during this study illuminates two different aspects of the Slit-Robo signalling system. Both of them, despite Slits being secreted proteins, hint at short-range, possibly even juxtacrine, ligand – receptor interactions. Given Robo receptor evolutionary connections to cell adhesion molecules and Slit affinity to heparan sulphate it is not a completely unexpected finding.

In this thesis was designed, manufactured and tested the fourth evolution of a slit-flow rheometer with another necessary parts, eg. rheometer`s holder, drive frame and important jig tools. The rheometer is able to measure rheological properties of magnetic and non-magnetic fluids at very high shear rates, which commercial rheometers can not reach. It is designed for 200 bar pressure and maximum load 15 kN. The construction of the slit-flow rheometer with it`s holder and drive frame improves user friendliness, accelerates change of the fluid sample and expands research opportunities thanks to a big space for additional adjustments. It is possible to use different length of the slit and thanks to a changeable inserts it is possible to change parameters of the slit (roughness of the walls, wall material, thickness of the slit). A part of this thesis was focused on illation of necessary equations for planning calibration measurements. Aim of these measurements is to obtain minor pressure losses dependence on Reynolds number for specific slit.

Structured light pattern projection techniques are well known methods of accurately capturing 3-Dimensional information of the target surface. Traditional structured light methods require several different patterns to recover the depth, without ambiguity or albedo sensitivity, and are corrupted by object movement during the projection/capture process. This thesis work presents and discusses a color multiplexed structured light technique for recovering object shape from a single image thus being insensitive to object motion. This method uses single pattern whose RGB channels are each encoded with a unique subpattern. The pattern is projected on to the target and the reflected image is captured using high resolution color digital camera. The image is then separated into individual color channels and analyzed for 3-D depth reconstruction through use of phase decoding and unwrapping algorithms thereby establishing the viability of the color multiplexed single pattern technique. Compared to traditional methods (like PMP, Laser Scan etc) only one image/one-shot measurement is required to obtain the 3-D depth information of the object, requires less expensive hardware and normalizes albedo sensitivity and surface color reflectance variations. A cosine manifold and a flat surface are measured with sufficient accuracy demonstrating the feasibility of a real-time system.

Digital imaging systems for medical applications must bebased upon highly efficient detectors to ensure low patientdose. This is particularly important in screening mammographybecause of the large number healthy women that is examined. Amammography system must also provide high spatial and contrastresolution. Different approaches are compared in this thesis,and it is argued that a system based on photon countingdetectors in a scanned multi-slit geometry provides aperformance superior to established technologies.

The system is realized using silicon strip detectorsirradiated at a small angle relative to the wafer surface,thereby offering large absorption depth. A linear pixelarray isscanned across the breast to obtain the complete image.Pulse-processing electronics rejecting all detector andelectronics noise count the number of photons that aredetected, forming the pixel values of the image.

Optimization of the detector design is discussed in detail.The detector has been carefully simulated to investigate chargemotion and signal formation after photoninteraction. Based onthese simulations, the impact of the detector characteristicson the image quality has been evaluated.

Detectors have been manufactured and evaluated both assingle components and as part of experimental imaging devicesincluding custom readout electronics. Presented in this thesisare the measured detector characteristics including a verifi-cation of charge collection efficiency and confirmation thatthe quantum efficiency is 90% for a typical mammographyspectrum. Modulation transfer functions and noise power spectrawere recorded and the detective quantum efficiency calculated.A prototype mammography system was also assembled and themodulation transfer function recorded. The interpretation ofthe modulation transfer function and detective quantumefficiency is discussed for digital systems in general and fora scanned multi-slit system in particular.

Keywords:x-ray, imaging, silicon, detector, digital,mammography, scanning, photon counting.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2008.
Includes bibliographical references (p. [135]-143).
The ability to visually observe single DNA molecules has greatly improved our understanding of polymer physics, from gel electrophoresis to the theology of dilute (and even concentrated) polymer solutions. The use of DNA in these general studies, though, resulted in a depth of specific knowledge concerning a particular polymer of major interest in biology. Researchers have taken advantage of this wealth of knowledge to develop new, faster, cheaper, and more direct methods of extracting the information, at a coarse level, embedded in the sequence of basepairs along the DNA backbone. Further development, though, is now limited by the ability to control and manipulate the position and conformation of single DNA molecules. It was recognized long ago that confinement of polymer molecules in geometries with dimensions on the order of the polymer size would greatly affect the physical behavior of that polymer. These physical changes were later hypothesized to be of use to control single molecules of DNA. However, until recently, the confinement theories and their use stood untested due to a lack of techniques to reliably and controllably construct micro- (and nano-) devices with such small feature sizes. It is the focus of this thesis to investigate these confinement effects in an ideal, nanofabricated geometry and their use in the manipulation and control of single DNA molecules. In this thesis, we present a series of single-molecule visualization studies aimed at elucidating polymer behavior in confinement and methods of possible use in the manipulation and control of the polymer conformation. In particular, confinement in a slit was shown, both experimentally and through scaling analysis, to diminish long length scale polymer-induced solvent flow sufficiently enough to render those effects negligible in the behavior of the confined molecule. We also demonstrate that confinement also alters the diffusion and relaxation time of the DNA, and we compare their dependence on channel height and molecular weight to existing theories.
(cont.) De Gennes' blob theory is found to describe the molecular weight scalings quite well, but predictions of the scalings with channel height are plagued by an oversimplified description of short length scale polymer-solvent interaction used in the theory. Thus, empirical knowledge is needed to adequately predict the scaling of DNA transport coefficients in confinement. We also investigate aspects of polymer deformation in confinement. We observe, for the first time, two slow modes of polymer relaxation. The two modes are found to govern polymer behavior based on the polymer's extension, a phenomenon unique to confinement in polymer physics. A simple, physical model is developed to explain the origin of the two governing time scales, to explain their scaling with channel height and molecular weight, and to predict the extension at which the exchange between the two timescales occurs. We also examine the effects of these two characteristic time constants on the steady-state stretch of molecules in confinement. We find that the second-longest relaxation time determines the deformation rate needed to unravel the coil, unlike bulk polymer deformation. Interestingly, details of this unraveling change significantly in confinement, highlighting the need for further work in this area. In larger channels, we demonstrate that microfabrication techniques in the form of an obstacle array with dimensions smaller than the polymer size can aid polymer stretching. While a polymer will often fold or kink during stretching, we find the use of a collision event to "precondition" the polymer conformation for stretching makes these folds and kinks less likely, and therefore, stretching occur more rapidly. The efficiency of the device depends strongly on the probability of a collision event, and results from single molecule/single post experiments are used to demonstrate the capability of a second-generation device. The impact of this thesis will be two-fold. Our fundamental results have and will continue to serve as a basis of comparison and a springboard for more complicated studies of confined polymer physics.
(cont.) These studies provide detailed information on DNA transport coefficients in geometries widely utilized in microfabricated devices. We also directly display the effects of confinement on DNA manipulation. Non-equilibrium polymer dynamics are found to be highly nontrivial, exemplified by the importance of a new timescale of polymer motion. Importantly, it is this new timescale that is of concern for applications such as gene mapping where large scale polymer deformation is required. Lastly, we demonstrate the success of a unit-operation-like approach to the design of polymer manipulation devices.
by Anthony Balducci.
Ph.D.

Den här studien undersöker vilka bakgrundsfaktorer som ligger bakom slit- och slängbeteende. Med hjälp av beteendeteorin Theory of Planned Behavior, intervjuer och observationer så visar studien att funktion och kvalitét måste samspela med kognitiv tillfredställelse för att någon ska vilja behålla en produkt länge. Studien finner även att människors sociala behov är en faktor som kan påverkas för att öka tiden som en person väljer att behålla en produkt. Målet med studien är att genom väletablerade teorier om emotionell design och tillfredsställning genom produkter presentera ett designkoncept som påverkar bakgrundsfaktorerna till slit- och slängbeteendet. Det uppnås genom att hitta en produktkategori bland artefakter som kastas. Det har framkommit att lampor är en sådan en sådan produkt. Designkonceptet som presenteras i den här studien är en bordslampa designad för att påverka bakgrundsfaktorerna som styr intentionen till att hålla kvar vid en produkt.
This study investigates the background factors behind wear and tear behavior. Using the behavioral theory Theory of Planned Behavior, interviews and observations, the study shows that function and quality must interact with cognitive satisfaction in order for someone to want to keep a product for a long time. The study also finds that people's social needs are a factor that can be influenced to increase the time a person chooses to keep a product. The aim of the study is to present, through well-established theories of emotional design and satisfaction through products, a design concept that influences the background factors for wear and tear behavior. This is achieved by finding a product category among discarded artifacts. It has emerged that lamps are one such product. The design concept presented in this study is therefor a table lamp designed to influence the background factors that control the intention to keep a product.

This work presents a comparative study between a sample of Seyfert galaxies and a control sample of galaxies that was done to determine if the presence of an active nucleus would in any way effect its host galaxy. An obvious manifestation of such an effect would be changes in the star formation properties of the Seyfert galaxies relative to the control sample. Since the star formation rate is directly related to the amount of Hα emission, the Hα luminosity along the major axis of each program galaxy was measured. The result of this work was twofold. First, a highly optimized CCD camera system was developed for use as a facility instrument. This camera system was then used to spectroscopically survey 15 Seyfert and 15 normal galaxies. Hα emission was measured in 12 Seyfert and 12 normal galaxies. It was found that after comparing a number of different quantities all dependent on the star formation process, there was no discernible difference between the sample of Seyfert galaxies and the sample of normal galaxies. In particular, the total Hα emission, line ratios and various properties of the sites of star formation and their spatial distribution were similar between the two samples. This implies that the disk regions of Seyferts are identical to the disks of normal spirals as determined by the properties of their giant HII regions.

Introdução: A avaliação dos processos inflamatórios em pacientes com tumores de boca é assunto atual na literatura científica. Poucos estudos, entretanto avaliaram a expressão da Proteína Inibidora de Protease Secretada por Leucócito (SLPI), marcador específico de inflamação, em pacientes com câncer de boca Objetivos: 1.Descrever a frequência da concentração de SLPI salivar e sérica em pacientes com câncer bucal. 2. Avaliar a associação dessas concentrações com características clínicas, sociodemográficas e de estilo de vida. Metodologia: Realizou-se a quantificação de SLPI em soro por meio do teste ELISA em pacientes com carcinoma epidermoide da cavidade bucal atendidos no Hospital Heliópolis da Secretaria de Estado da Saúde do Estado de São Paulo no período entre 2011 e 2017. Dados relativos a estadiamento do tumor, características sócio demográficas dos pacientes, hábitos alimentares e estilo de vida foram coletados por meio de prontuários médicos e questionários aplicados aos pacientes. Foram realizados teste de correlação de Spearman e teste qui-quadrado para testar possíveis associações. Resultados: Foram encontradas: correlação positiva entre SLPI em saliva maços-ano de tabagismo (p=0,03) e correlação negativa entre SLPI bochecho para frequência no consumo de carne vermelha (p=0,01). A quantificação de SLPI em soro por quartis apresentou associação com significância estatística para escolaridade (maior proporção de pessoas com ensino médio completo no quartil mais baixo de SLPI), frequência de escovação dentária (maior proporção de pessoas que escovam os dentes mais do que uma vez por dia no quartil com maior SLPI) e estadiamento patológico (2º quartil com maior proporção de estadiamentos 3 e 4). Na avaliação de SLPI em saliva e bochecho, houve associação com o consumo de carne vermelha, havendo indivíduos com consumo mais baixo apenas nos quartis mais superiores de SLPI Conclusão: Este estudo concorda com a hipótese de que o SLPI em pacientes com câncer de boca se relaciona com estilo de vida e estadiamento da lesão.
Introduction: The evaluation of inflammatory processes in patients with oral tumors is a current topic in the scientific literature. Few studies, however, have evaluated the expression of the Leukocyte Secreted Protein Inhibitor Protein (SLPI), a specific marker of inflammation in patients with oral cancer. Objectives: 1. To describe the frequency of salivary and serum SLPI in patients with oral cancer. 2. To evaluate the association of these concentrations with clinical, sociodemographic and lifestyle characteristics. Methodology: Serum SLPI was quantified by ELISA in patients with squamous cell carcinoma of the oral cavity treated at the Hospital Heliópolis of the State Health Department of the State of São Paulo in the period between 2011 and 2017. Data on staging of the tumor, socio-demographic characteristics of patients, eating habits and lifestyle were collected through medical records and questionnaires applied to patients. Spearman\'s correlation test and chi-square test were performed to test possible associations. Results: There was a positive correlation between SLPI in saliva and malnutrition SLPI (p = 0.03). The quantification of SLPI in serum by quartiles was associated with statistical significance for schooling (higher proportion of people with complete secondary education in the lowest quartile of SLPI), frequency of toothbrushing (a higher proportion of people brushing their teeth more than once per day in quartile with higher SLPI) and pathological staging (2nd quartile with a higher proportion of stages 3 and 4). In the evaluation of SLPI in saliva and mouthwash, there was an association with red meat consumption, with individuals with lower consumption only in the higher quartiles of SLPI. Conclusion: This study agrees with the hypothesis that SLPI in patients with oral cancer is related to lifestyle and staging of the lesion.

Healthy pre-natal development of the mammalian visual system requires that retinal ganglion cell (RGC) axons navigate a precise path to their targets in the thalamus and superior colliculus by making a precise series of turns determined by the complex interactions between growth cone and extracellular environment. One important choice point for RGC axons is the crossing of the midline at the optic chiasm, where ipsilateral/ contralateral sorting takes place. In this thesis a novel image analysis method using steerable filters for quantifying the gross orientation and turning of axons from a static image (such as from DiI filled axons) is presented. This method was applied to understanding Slit dependent axon guidance at the mouse optic chiasm. It was possible to quantify the differences at the chiasm between the wildtype and various classes of mutants involving heterzygous or homozygous knockout of the Slit1 and the Slit2 genes. Assessment was in terms of the spatial distributions in axon density and axon orientation as derived from DiI labeled RGCs originating from one eye. The animals were assessed at embryonic day 13.5. To my knowledge this is the first quantification of its kind in the field of axon guidance. It was found that there were strong statistical differences from wildtype in both the Slit1-/-;Slit2-/- and Slit1+/+;Slit2-/- knockouts in terms of both axon density and axon orientation across large extents of the chiasm. In both these knockouts it was found that the changes in axon density were localised to the anterior region of the chiasm, but the changes in axon orientation were spread across almost the entire extent of the chiasm. No other combination of the Slit1 and Slit2 knockouts for which embryos could be generated showed significant differences from wildtype in terms of spatial changes in axon density or axon orientation. No embryos were generated for the Slit1+/-;Slit2-/- combination. No changes in the spatial distribution of axon density or axon orientation were found between the Slit1-/-;Slit2-/- and Slit1+/+;Slit2-/- knockouts, suggesting that in terms of these two quantities, the two phenotypes are indistinguishable. This evidence suggests that the role of Slit2 is more important than the role of Slit1 at the optic chiasm in terms iii of axon guidance. In addition, the gradients of mRNA expression of Slit1 and Slit2 were quantified using in situ hybridisation, and these data were used to compare the mRNA gradients with the orientation and turning of axons in both the wildtype and Slit1/Slit2 knockout chiasms. Although this provided a powerful visualisation tool, no simple mathematical relationship was found between the mRNA gradient of Slit1 or Slit2 and the orientation or turning of axons at the optic chiasm. These approaches now provide an important suite of methods for spatial analysis of axon tracts and molecular gradients in axon guidance.

Using the genome database of the phytopathogenic fungus, Alternaria brassicicola, we identified a gene with high homology to the cell wall integrity-associated mitogen-activated protein (MAP) kinase, Slt2 in the yeast, Saccharomyces cerevisiae. This MAP kinase consists of a predicted 1,251-bp open reading frame, and encodes a 416-amino-acid protein weighing 47501 Da. This homolog was designated AbSlt2 (A. brassicicola Slt2) and gene disruption knockout (KO) mutants were generated in an A. brassicicola wild type background. Several altered phenotypes were found in the mutants compared to the wild type. During growth in various liquid and solid media, the abslt2 mutants displayed slightly aberrant hyphal growth and were unable to develop at the same rate as wild type. Furthermore, scanning electron microscopy (SEM) analysis revealed the abslt2 mutants showed decreased penetration ability, underdeveloped appresoria, and altered morphology on the leaf surface of the host plant, Brassica oleracea (cabbage) when compared to wild type. Abslt2 mutant hyphae exhibited slower growth in planta ultimately resulting in highly reduced virulence. Complementation of the disruption mutant with the wild type gene fully restored pathogenicity. Therefore, AbSlt2 is a new pathogenicity and developmental factor in A. brassicicola.
Master of Science

Le sang est une suspension concentrée (45 % en volume) de cellules déformables, les globules rouges, dans un liquide newtonien, le plasma. Dans la microcirculation, i.e. le sous-ensemble du système de circulation sanguine où s'effectuent les échanges de matière entre le sang et les tissus, les tailles de vaisseaux sont comparables à la taille d'un globule rouge (environ 10 µm). En conséquence, les effets dynamiques liés à la présence de ces cellules induisent des comportements rhéologiques complexes, qui jouent un rôle important dans le transport de l'oxygène vers les tissus. En particulier, aux bifurcations microvasculaires divergentes, les débits de globules rouges et de plasma peuvent se répartir de façon non proportionnelle entre les deux branches filles. La fraction volumique de globules rouges (hématocrite) dans l'une des branches filles est alors plus élevée que celle de la branche d'entrée, et la fraction volumique dans l'autre branche y est plus faible. Cet effet, connu sous le nom d'effet de séparation de phase, induit une très grande hétérogénéité de l'hématocrite d'un vaisseau à l'autre dans la microcirculation. Il induit également un couplage entre l'architecture du réseau microvasculaire et la dynamique de l'écoulement sanguin dans ce réseau. L'objectif de ce travail de thèse est d'étudier finement l'effet de séparation de phase in vitro, dans un régime représentatif des conditions physiologiques, au moyen de dispositifs microfluidiques modélisant les bifurcations microvasculaires et de suspensions de globules rouges. Dans ce but, un dispositif expérimental microfluidique a d'abord été élaboré. Puis, les aspects métrologiques spécifiques aux suspensions concentrées ont été abordés afin de quantifier les paramètres de l'écoulement. En particulier, la technique de dual-slit a été comprise et optimisée, assurant une mesure précise de profils de vitesse de globules rouges en microcanaux. Des métrologies spécifiques à nos conditions expérimentales ont également été mises en place pour déterminer l'hématocrite. Ces techniques ont été validées par vérification du principe de conservation de la masse entre les trois branches d'une bifurcation, et elles nous ont permis de caractériser les écoulements de globules rouges dans des micro-canaux de différentes tailles (10 à 100 µm), et ce pour de larges gammes de débits et de concentrations. Enfin, l'écoulement de suspensions de globules rouges a été étudié au niveau de micro-bifurcations, dans l'objectif de caractériser l'effet de séparation de phase pour des tailles de canaux et des gammes d'hématocrites qui n'ont pas été étudiés auparavant en conditions d'écoulement maîtrisées
Blood is a concentrated suspension (45% by volume) of deformable red blood cells, flowing in a Newtonian fluid called plasma. The microcirculation is the part of the blood circulation system where the exchanges of material (e.g. nutrients, oxygen) between the blood and tissues take place. The microvessels are characterized by diameters less than 100 microns, which is similar in size to the size of a red blood cell ( 10 microns). As a result, the presence of these cells considerably influences the dynamics of microvascular flows and induces complex rheological behaviors. In particular, at diverging microvascular bifurcations, red blood cells and plasma may be nonproportionally distributed between two daughter vessels : one gets a higher red blood cell volume fraction (hematocrit) than the feeding vessel, while the other gets a lower one. This effect, known as the phase separation effect, causes a tremendous heterogeneity of the hematocrit among vessels in microvascular networks and induces a coupling between the microvascular architecture and the blood flow dynamics. The aim of this thesis is to investigate the phase separation effect in vitro, in physiological conditions, using red blood cell suspensions and microfluidic devices modeling microvascular bifurcations. For this purpose, a microfluidic experimental device was first developed. Then the metrological aspects specific to concentrated suspensions were addressed in order to quantify all the flow parameters. In particular, the dual-slit technique has been understood and optimized, ensuring accurate measurement of velocity profiles of red blood cells in microchannels. Measurement methods for our experimental conditions were also implemented to determine the hematocrit. All these techniques have been validated by verification of the principle of mass conservation between the three branches of a bifurcation. They allowed us to characterize the flow of red blood cells in microchannels of different sizes (10 to 100 microns) and for wide ranges of flow rates and concentrations. Finally, the flow of red blood cell suspensions was investigated at micro-bifurcations, with the aim of characterizing the phase separation effect for channel sizes and hematocrit ranges never studied in controlled flow conditions

Secretory leucoprotease inhibitor (SLPI) has multifaceted roles in protecting tissues from the damaging effects of inflammation. In addition to its well characterised role as a protease inhibitor, SLPI has been shown to have anti-inflammatory and anti-microbial properties. The therapeutic potential for SLPI as an anti-inflammatory treatment has previously been assessed in chronic inflammatory conditions and has shown promising results in a clinical trial with cystic fibrosis (CF) patients. There is evidence to suggest that SLPI can also inhibit acute inflammation; however the administration of exogenous SLPI as a therapy during the acute inflammatory response has never been investigated. The work presented in this thesis establishes recombinant human SLPI (rhSLPI) as a wide-acting anti-inflammatory following both systemic and pulmonary inflammation induced by bacterial cell surface components. Additionally, rhSLPI was able to reduce a number of inflammatory parameters following pulmonary Pseudomonas aeruginosa infection; however it had no effect on bacterial burden. It was noted that despite reductions in known pro-inflammatory markers, IL-17 was increased following rhSLPI treatment. This IL-17 was shown to be from double negative (ON) T cells, which have been previously reported to play a protective role following pulmonary infection. The importance of SLPI as an inflammatory regulator is established through the increased susceptibility of SLPI knockout (KO) mice to LPS-induced lung inflammation as well as Pseudomonas and Staphylococcus pulmonary infection. Together this gives evidence that SLPI modulates the acute inflammatory response. It should therefore be considered as an anti-inflammatory therapeutic for acute sterile conditions, such as pancreatitis, or acute infections such as that seen in acute respiratory distress syndrome (AROS) patients where it could be combined with antibiotics.

Chez les mammifres, le cerveau postnatal contient des régions o la prolifération sont maintenues, telle que la zone sous-ventriculaire (ZSV) ou bien la zone sous-granulaire (ZSG) capable de produire des nouveaux neurones du bulbe olfactif (BO) ou du gyrus denté (DG). De plus, le DG est généré en grande partie de faon postnatale. Mon projet visait à étudier le rôle joué par les molécules Slits et Robos dans le télencéphale postnatal et adulte, en particulier la neurogense. En utilisant une approche génétique in vivo, nous avons généré des lignées de souris mutantes pour les Slits et Robos (déficientes et conditionnelles) que nous avons croisé avec des souris exprimant la recombinase Cre dans la ZSV, le BO et le DG/ZSG. Dans ces animaux, l'absence de Slits/Robos provoque de sévères anomalies du développement des commissures télencéphaliques semblables à celles décrites chez les KOs. L'absence de certaines molécules Slits/Robos du télencéphale dorsal s'accompagne d'un défaut de migration des neurones de la ZSV, mais avec un effet moindre sur leur prolifération. Aussi, chez certaines souris déficientes pour Robos , nous avons observé une diminution du nombre de neurones granulaires dans le DG et dans le BO. En outre, les résultats obtenus à partir de la lignée Foxg1::Cre;Slit2lox/lox démontrent une baisse du nombre de nouveaux neurones provenant de la ZSV et une réduction de la neurogense hippocampique. L'hippocampe des souris Foxg1::Cre;Slit2lox/lox est de taille normale à la naissance, mais très réduit chez l'adulte. En conclusion, j'ai réalisé une des premires caractérisation du rôle in vivo des protéines Slits et Robos dans le télencéphale postnatal
In mammals, the postnatal brain contains regions where proliferation is maintained, such as the subventricular zone (SVZ) or sub-granular zone (SGZ) which are capable of producing new neurons of the olfactory bulb (OB) or dentate gyrus (DG). In addition, the DG is mostly generated postnatally. My project was to investigate the role played by Slit and Robo molecules in the postnatal and adult forebrain, particularly in neurogenesis. Using a genetic approach in vivo, we generated mutant mouse lines for Slits and Robos (deficient and conditional) that we crossed with mice expressing Cre recombinase in the SVZ, the OB and the DG/SGZ. In these animals, the absence of Slits/Robos causes severe developmental abnormalities of the forebrain commissures similar to those described in full knockouts. The absence of certain Slit/Robo molecules in the dorsal telencephalon is linked with defects in neuronal migration of SVZ-derived cells, but barely any effect on their proliferation. Also, in some mice deficient for Robos, we observed a decrease in the number of granule neurons generated in the DG and in the OB. In addition, the results obtained from the line Foxg1::Cre; Slit2lox/lox show a decrease in the number of new neurons from the SVZ and reduced hippocampal neurogenesis. The hippocampus of mice Foxg1::Cre;Slit2lox/lox is of normal size at birth, but very small in adults. In conclusion, I have performed one of the first in vivo characterizations of the role of Slits and Robos proteins in the postnatal forebrain

Includes abstract.
Includes bibliographical references (leaves 112-117).
This study describes dose measurements made for linear slit scanning radiography (LSSR) and a dose prediction model that was developed for LSSR. The measurement and calculation methods used for determining entrance dose and effective dose (E) in conventional X-ray imaging systems were verified for use with LSSR. Entrance dose and E were obtained for LSSR and compared to dose measurements on conventional radiography units. Entrance dose measurements were made using an ionisation chamber and dosemeter; E was calculated from these entrance dose measurements using a Monte Carlo simulator. Comparisons with data from around the world showed that for most examinations the doses obtained for LSSR were considerably lower than those of conventional radiography units for the same image quality. Reasons for the low dose obtained with LSSR include scatter reduction and the beam geometry of LSSR. These results have been published as two papers in international peer reviewed journals. A new method to calculate entrance dose and effective dose for LSSR is described in the second part of this report. This method generates the energy spectrum for a particular set of technique factors, simulates a filter through which the beam is attenuated and then calculates entrance dose directly from this energy spectrum. The energy spectrum is then combined with previously generated organ energy absorption data for a standard sized patient to calculate effective dose to a standard sized patient.Energy imparted for different patient thicknesses can then be used to adjust the effective dose to a patient of any size. This method is performed for a large number of slit beams moving across the body in order to more effectively simulate LSSR. This also allows examinations with technique factors that vary for different parts of the anatomy to be simulated. This method was tested against measured data and Monte Carlo simulations. This model was shown to be accurate, while being specifically suited to LSSR and being considerably faster than Monte Carlo simulations.

Zymoseptoria tritici est l'un des dix plus importants champignons pathogènes des plantes. Son impact économique sur la production de blé et ses caractéristiques biologiques (dimorphisme levure-hyphae, hémi-biotrophie, populations sexuées et diversifiées) fait de Z. tritici un organisme unique parmi les champignons pathogènes des plantes. Au cours des dix dernières années, il a suscité un intérêt croissant de la communauté scientifique conduisant au développement d'outils génomiques et génétiques. Ces efforts ont permis de mieux comprendre les mécanismes impliqués dans sa pathogénie et son évolution. Nous avons focalisé notre étude sur les trois «Mitogen-Activated Kinases» (MAPK) ZtFus3, ZtHog1 et ZtSlt2 de Z. tritici nécessaires au succès de l’infection. Nous avons réalisé une caractérisation phénotypique détaillée du mutant de délétion ZtSLT2 lors de l'infection du blé et du développement fongique in vitro. Nous avons montré que le mutant ΔZtslt2 est non pathogène pour les feuilles de blé, même lorsque la pénétration stomatique est court-circuitée par injection de spores dans la feuille, ce qui suggère que ce mutant présente un défaut dans la colonisation des tissus de la plante. Pendant la croissance in vitro, ZtSLT2 est nécessaire à la pigmentation, des colonies, l’émergence des hyphes aériens, la formation de biofilm et l’hydrophobicité de la colonie. Ces phénotypes sont des marqueurs d'un processus développemental qui se produit pendant le vieillissement de la colonie de Z. tritici (développement de colonies pigmentées et hydrophobes portant des hyphes aériens blancs). Ce processus développemental survient à des moments différents selon le milieu de culture et la température, le plus rapide étant sur milieu pauvre «Pomme de terre Glucose» (PD) à 25 °C (4 jours) et le plus lent sur milieu riche complet «Extrait de Levure, Peptone, Glucose» (YPD) à 18 °C (18 jours). Nous avons montré que les gènes codant pour des enzymes impliquées dans la biosynthèse de la mélanine, des α-1,3-glucanes et des hydrophobines sont surexprimées au cours de ce processus développemental dans la souche sauvage, en particulier après trois jours de culture sur PD à 25 °C par rapport aux autres conditions. Cette surexpression nécessite que la voie ZtSLT2 soit fonctionnelle. L’analyse transcriptomique (RNAseq) de ces conditions différentielles est en cours pour identifier le réseau de gènes nécessitant la protéine Slt2 pour leur expression. Ces gènes cibles de ZtSLT2 sont des facteurs de pathogénicité putatifs.Nous avons également développé un nouvel outil moléculaire pour Z. tritici. Nous avons montré que les promoteurs pMoNIA1 et pZtNIA1 des gènes codant les nitrates réductases de Magnaporthe oryzae et Z. tritici, respectivement, sont régulés par la source d’azote du milieu de la même façon chez Z. tritici. L’expression de gènes sous le contrôle de ces deux promoteurs est maximale en présence de nitrate comme seule source d'azote, mais réduite en présence de glutamate. Ces promoteurs peuvent donc être utilisés pour l'expression conditionnelle de gènes et le remplacement de promoteur chez Z. tritici. Ils seront utiles pour contrôler l'expression des allèles constitutivement actifs des MAP kinase kinases dans le but d’activer les voies des MAPK de manière conditionnelle
Zymoseptoria tritici is one of the ten more important fungal plant pathogens. Its economic impact on wheat production and its biological characteristics (yeast-fungal dimorphism, hemi-biotrophy, sexual and highly diverse populations) make Z. tritici unique among fungal plant pathogens. It has therefore drawn attention of the scientific community during the last ten years, leading to the development of genomic and genetic tools. These efforts have improved our understanding of its pathogenicity and evolution. We have focused our study on the three Z. tritici Mitogen-Activated Protein Kinase (MAPK) signalling pathways (ZtFUS3, ZtHOG1, and ZtSLT2) which are required for pathogenicity. We provided novel insights in the role of ZtSlt2 MAPK signalling pathway using a detailed phenotypic characterization of SLT2 deletion mutant during wheat infection and in vitro development. We showed that SLT2 is non-pathogenic on wheat leaves, even when stomatal penetration is bypassed by spore injection, suggesting a defect in leaf colonisation. During in vitro growth, SLT2 is required for melanisation, aerial hyphae emergence, biofilm formation and colony hydrophobicity which are markers of a developmental switch occurring during Z. tritici colony aging (development of melanised and hydrophobic colonies supporting abundant white aerial hyphae). This developmental switch occurs at different times depending on media and temperatures, quickest being on poor plant-derived Potato Dextrose (PD) medium at 25°C (4 days) and slowest on rich complex Yeast Extract Peptone Dextrose (YPD) medium 18°C (18 days). We provided evidence that genes encoding enzymes involved in both melanin and α-1,3-glucan biosynthesis, and hydrophobins are up-regulated during this developmental switch in wild type, in particular at 3 days on PD at 25°C compared to other conditions. This up-regulation clearly requires a functional ZtSLT2 pathway. Transcriptomic analysis (RNAseq) of these differential conditions is ongoing to identify the network of genes requiring SLT2 for their expression. These SLT2 target genes are putative pathogenicity factors. We also provide a new molecular tool for Z. tritici. We showed that pMoNIA1 and pZtNIA1 promoters from nitrate reductases encoding genes of Magnaporthe oryzae, and Z. tritici, respectively, are nitrogen-responsive in Z. tritici to a similar extent. They are fully expressed in presence of nitrate as sole nitrogen source and down-regulated in presence of glutamate, showing they are suitable for conditional gene expression and promoter replacement in Z. tritici. These promoters will be useful to control the expression of constitutively active alleles of MAP Kinase kinases in order to activate MAPK pathways in a conditional manner

In this dissertation, imaging characteristics of a nano-slit are investigated. Applications of a scanning and rotating nano-slit in measuring sub-micron aerial features are demonstrated. Coherent sub-micron spot distributions are reconstructed with a very high contrast. Finally, high NA partially coherent images with features as small as 210 nm half-pitch are reconstructed and the ultimate resolution of the system is determined.A nano-slit is characterized as a sensor for coherent line-and-space features. Experiments and simulation verify image detection with contrasts greater than 0.9. Effects of polarization on imaging performance are reported. A scanning and rotating nano-slit in conjunction with a filtered back-projection technique is used to reconstruct sub-micron coherent spot distributions. Simulation results show very good agreement with the experiment. Further, it is shown that the reconstruction is very resilient to some common random experimental errors.Imaging characteristics of a scanning nano-slit sensor are determined for high NA partially coherent images. Good imaging performance (contrast > 0.8) is demonstrated with line-and-space images up to a spatial frequency of 2.38 lp / micron. Sub-micron features in a high NA partially coherent image are measured with a scanning and rotating nano-slit. A modified microscope is used to create the measured features, including 210 nm half-pitch features that cannot be imaged using the microscope in a conventional imaging mode. Using the filtered back projection technique, two-dimensional sub-micron features are reconstructed by the nano-slit sensor. It is determined that the resolution limit of ~ 200 nm is determined by the reconstruction technique and not by the width of the nano-slit.

The construction of 3D models of real-world scenes using non-contact methods is an important problem in computer vision. Some of the more successful methods belong to a class of techniques called structured light illumination (SLI). While SLI methods are generally very successful, there are cases where their performance is poor. Examples include scenes with a high dynamic range in albedo or scenes with strong interreflections. These scenes are referred to as optically challenging environments. The work in this dissertation is aimed at improving SLI performance in optically challenging environments. A new method of high dynamic range imaging (HDRI) based on pixel-by-pixel Kalman filtering is developed. Using objective metrics, it is show to achieve as much as a 9.4 dB improvement in signal-to-noise ratio and as much as a 29% improvement in radiometric accuracy over a classic method. Quality checks are developed to detect and quantify multipath interference and other quality defects using phase measuring profilometry (PMP). Techniques are established to improve SLI performance in the presence of strong interreflections. Approaches in compressed sensing are applied to SLI, and interreflections in a scene are modeled using SLI. Several different applications of this research are also discussed.

The analysis of extrudate swell in polymer melts is of great importance in many polymer processing operations and has been the subject of interest both experimentally and numerically. The main objectives of this research work are to obtain systematic and reliable extrudate swell data of a high molecular weight HDPE, to identify a suitable constitutive model that can precisely represent extrudate swell phenomena and to predict extrudate swell accurately under various processing and operating conditions. A novel extrudate swell measuring system with an online data acquisition system is designed for the present work. This system allows one to measure extrudate swell profile under different conditions such as steady state or transient, gravity free, isothermal and non-isothermal conditions. Further, the set-up is suitable for both capillary and slit extrudates. A comprehensive analysis on the applicability and validity of various rheological (integral and differential/molecular) models in describing extrudate swell of a highly viscoelastic HDPE polymer over a broad range of shear rates (5 to 100s-¹) is carried out using FEM based ANSYS POLYFLOW®. The simulation results indicated that the integral constitutive equations of K-BKZ type can account for the significant memory effects of viscoelastic polymer melts such as HDPE. Overprediction of extrudate swell by the integral K-BKZ model invoked the importance of obtaining non-linear viscoelastic properties for a broader range of deformations/deformation rates. The newly available CPP fixture from AntonPaar is used to procure such non-linear viscoelastic data and thus to determine the accurate damping function. The simulation results of extrudate swell in capillary and slit dies are in good agreement with the experimental measurements using the newly determined damping function. In addition, non-isothermal extrudate swell of the HDPE polymer is studied using the pseudo-time integral K-BKZ Wagner (i.e., the non-isothermal form) model with the differential Nakamura equation for the crystallization kinetics. The model is implemented in ANSYS POLYFLOW®. Extrudate swell measurements are obtained by extruding the polymer melt at 200ºC through long capillary and slit dies to ambient air at 25ºC and 110ºC. The numerical results are found to be in very good agreement with the experimental observations.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate

Ce travail vise à étudier les propriétés de transport et le comportement poromécaniquede fluides simples confinés dans des nanopores lamellaires par le biais de simulationsmoléculaires. Pour ce faire, nous avons proposé différents schémas de simulations de ladynamique moléculaire dans des ensembles adaptés aux propriétés étudiées (diffusion demasse, viscosité, force de friction, gonflement …). Il a été note que les propriétés de transportde fluides fortement inhomogènes variaient fortement dans la direction perpendiculaire auxmurs solides. Nous avons alors proposé une approche non-locale permettant de déterminerquantitativement la viscosité locale de fluides inhomogènes à partir du profil de densité etapplicable pour des sphères dures, molles et le fluide de Lennard-Jones. Il a été égalementmontré qu’un fluide de Lennard-Jones fortement confiné pouvait avoir un comportementviscoplastique (et rhéofluidifiant) si un ordre structurel était induit dans le fluide par laposition relative des murs solides. Enfin, nous avons montré qu’une modification importantede la pression de solvatation du fluide confiné peut être induite par cisaillement ce qui peutinduire un gonflement « dynamique » d’un nanopore lamellaire
This work aims at investigating the transport properties and the poromechanics of simple spherical fluids confined in slit nanopores through molecular simulations. To do so, we have proposed different schemes to perform molecular dynamics simulations in ensembles adequate to deal with the properties we were looking after (mass diffusion, shear viscosity,friction force, swelling …). The transport properties of strongly inhomogeneous fluids were found to be varying with space perpendicularly to the solid walls. We have then proposed a non-local approach to determine quantitatively the local shear viscosity of such inhomogeneous fluids from the density profile applicable from the Hard-Sphere to the Lennard-Jones fluids. In addition, it has been shown that highly confined Lennard-Jones fluid may exhibit a visco-plastic (+ shear thinning) behavior when a strong structural order is induced in the whole confined fluid because of the relative position of the solid walls. Finally, it was demonstrated that shear induced modifications of the solvation pressure of a confined fluid may exist that leads to a “dynamic” swelling when a slit micropore is sheared

Abstract: Over-the-horizon radars (OTHRs) are HF-band systems that, via surface propagation (ground-wave or surface-wave) or ionospheric re ection (sky-wave), cover an area that is located well beyond the horizon. Though based on an assessed technology, OTHRs are attracting today much interest, thanks to the relevant improvements in signal processing and data storage techniques. By exploiting the propagation mechanisms of HF waves in the Terrestrial Atmosphere, the OTHR is able to overcome the horizon line, that represents a natural boundary for every ground-based microwave radar. In the case of sky-wave OTHR, the re flection of the signals by the Ionosphere allows the system to achieve range distances up to about 3000 km. Nevertheless, the employment of the Ionosphere as part of the propagation-channel introduces an intrinsic uncertainty about the actual HF wave propagation path and, consequently, about the actual geographic position of the radar footprint. In fact, the non-homogeneous structure and time-dependent behavior of the Ionosphere make the a priori models for the propagation channel absolutely useless for a correct Geo-referencing of the received echo. Therefore, every HF OTHR-SW application must include a process to associated the received signals to unambiguous geographic coordinates. Such a process, referred to as coordinate registration (CR), generally relies on an ionospheric model, based on seasonal and daily ionospheric statistics within the radar operating area. Several current OTHR-SW systems perform a periodic update of the ionospheric model exploiting information gathered by ionosonde networks or directly collected from the OTHR with a dedicated procedure. Both approaches exhibit several limitations, leading to a correct characterization of the ionosphere only when it is in particularly steady conditions. The present research is focused on the study and development of a new different approach to the CR problem for OTHR-SW systems. This approach, referred to as Sea/Land Transition Identification (SLTI), takes advantage from the a priori knowledge of the Geo-morphological structure of the surveillance area in order to compensate for the uncertainties introduced by the Ionosphere. In fact, as suggested by the name of the method, the shape of the coastline profiles within the surveillance area are employed as position-references for the geo-referencing of the received radar echo. This task is possible through a basic time analysis of the echo, thanks to the marked difference in the values of the HF back-scattering coefficient for sea and land regions. The SLTI method is based on the maximization of the cross-correlation between the received radar echo and the surface mask signatures for the surveillance area. It can be employed in real time by the system, during its typical surveillance routine and besides the collected data can be exploited to estimate some Ionospheric parameters in order to periodically update and correct the employed statistical model. After a general introduction about the OTHR sensors and a more detailed description of the sky-wave system who we refer to in the present work, the state of the art for the CR procedures actually employed by OTHR-SW is presented. Hence the SLTI method is outlined together with the numerical model of the whole OTHR-SW scenario. The application of the method, in this scenario simulated under simplifying operative hypothesis, is described with the help of some examples for both the CR procedure and the Ionospheric probing task. Within these examples of application of the SLTI method, the minimum requirements in terms of received signal-to-noise ratio (SNR) and differential sea/land backscattering coefficients necessary to achieve a given accuracy in the range estimate are pointed out. Finally the further developments of the SLTI method and some possible improvement of the simulated OTHR-SW's scenario are pointed out.

The processing of the digital image brought new ways for all the known media to adapt to this new reality. The study of the digital media is not yet over and is to prove that the slit-scan technique still has many ways to develop that we create this study. We present the state of the of the slit-scan technique, not forgetting to mention the history of the image registration till it gets to the digital world. It’s also needed to present the concept of movement that is one of the most important subjects about slit-scan. Guestbook, the project made for the Master in Sound and Image will also be presented as it was developed side by side, using the same subject and investigation. In the end some research will be presented, identifying the development of some techniques and it’s results. During the research and the Dissertation some questions were tried to answer: -What is slit-scan and what is it useful for? -How can we use slit-scan in Science or in Art? -In how many ways can we use this technique and in what do they result? -Are there any new ways to progress with the slit-scan technique?
A presente Dissertação centra-se na técnica Slit-scan, introduzindo-a a partir das diversas etapas que levaram à sua origem. Da introdução dos conceitos básicos do movimento, até à origem da Fotografia, é apresentado o caminho artístico e cientifico que tornou possível o desenvolvimento de uma técnica que sem querer abriu uma porta para uma nova dimensão espácio-temporal. O Slit-scan tornou possível ao longo da história da arte do séc. XX uma nova percepção do tempo, do espaço e do movimento, representa-os de uma forma inovadora e que ultrapassou as barreiras do real. Os projectos artísticos apresentados demonstram diversos tipos de utilização e diversos tipos de resultados, em que a mais pequena alteração numa das variáveis cria uma nova janela para essa dimensão desconhecida. A apresentação do projecto Guestbook é referida, não só por ter sido um projecto que se desenvolveu ao mesmo tempo que a presente dissertação, mas porque explora uma vertente mais abrangente da técnica slit-scan. A Dissertação termina com uma análise dessa técnica – do tipo de utilizações e resultados, tentando responder à questão sobre as potencialidades do slit-scan ainda por explorar. São apresentados alguns resultados desse desenvolvimento

碩士
國立中興大學
水土保持學系
89
The channel structures for retaining debris flow can be categorized as permeable dam and impermeable dam. Usually, slit dam (permeable dam) is more efficient than the check dam (impermeable dam). Despite of their advantages, slit dams are often blockaded by boulder. In this study, slit dam with varied slit width, i.e., slits of different heights, was proposed to achieve the safe and economical objectives. To ensure the stability of slit dam with varied slit width, four different conditions with two different heights were analyzed in this study: (1) filled dam with normal flow under maximum earthquake, (2) filled dam with maximum flow, (3) empty dam impacted by debris flow, and (4) nearly filled dam striken by giant boulder at the top of dam. For illustrative purpose, an 8 meters high slit dam with varied slit width under condition (4) was designed to illuminate the mechanics analysis, thickness of the dam at different elevation, and the reguired amounts of steel bar. Finally, this study indicates that slit dam with varied slit width can achieve the safety objective with lower cost than traditional slit dam does.

碩士
國立臺北藝術大學
科技藝術研究所碩士班
95
The concept for Floating came from the absent minded state that happens during movement. I usually daydream while I travel, and I feel as if I am having an out of body experience that is impossible to describe with words. As physics explains, when a person is being transported a perceptual paradox is produced. For example, while we are riding in a vehicle our vision and conscious mind tell us that we are moving, but we have the feeling that our bodies are motionless within the vehicle. Therefore, our perception creates this discrepancy or paradox of simultaneous motion and stillness. In my own experience, while working in front of my computer for long hours, playing computer games or using messaging software, I often have the same sensation. Since I am looking into the illusory space inside of the computer and my body isn’t actually moving, the same kind of perceptual discrepancy is produced. Ordinarily, during my work time or when I am just sitting in front of the computer, I often use a messaging program to chat or communicate with other people. In this third body condition, I am present but have no physical presence. There’s no time difference problem, it’s just that you don’t think about sleep until you’re tired. If you were to transform this experience into a visual idea, it would be like I am traveling down a virtual road and a great number of digital signals pass through my brain, ceaselessly getting sucked in. The body (the immaterial body) floats along this thoroughfare without a feeling of time. I try to take these firsthand experiences in the digital world and extend and assemble them into the concept of floating in my work. In the series Floating Project, I have tried to combine applications of technological media to express this idea of perceptual paradoxes. This situation could be a kind of perceptual experience in everyone’s life, like being in a trance or daydreaming. In this series, I utilize my own perceptions and technology to explain this kind of experience.

碩士
國立成功大學
航空太空工程學系碩博士班
96
The phenomenon of vortex shedding due to uniform flow over a circular cylinder with a normal slit was investigated in this study. Experiments were made for five cylinder models whose slit widths in terms of s/d, where s and d denote the width and the cylinder diameter, respectively, were 0, 0.05, 0.15, 0.20 and 0.30. For the experiments made in a water channel, the techniques of Particle Image Velocimetry (PIV) and flow visualization were employed. The PIV data obtained at the Reynolds numbers between 2,400 and 11,400 reveal a trend that the vortex shedding frequency reduced gets increased as s/d gets higher. More interestingly noted is that for the case of s/d= 0.15, the process of vortex shedding appears to be most periodic in time, which quantitatively can also be indicated by the signal quality defined. Results of flow visualization indicate that flow in the slit is oscillating in accordance with the frequency of vortex shedding, which in fact causes suction or blowing to flow over the circular cylinder. Thus, unsteady motions in the slit are realized very effective to modify the vortex shedding process. Experiments made in a wind tunnel were aimed to examine the two-dimensionality of vortex shedding by means of spanwise correlation of hot-wire measurements at the Reynolds numbers between 30,000 and 50,000, for the five cylinder models studied. Results obtained indicate that the vortex shedding structures in the case of s/d=0.15 behave most two-dimensional. Hilbert-Huang Transformation (HHT) analysis of the velocity signals measured further show that among the five cases studied, the case of s/d=0.15 appears to be the one whose instantaneous vortex shedding frequency is most stabilized in time and its amplitude is the highest in value.

碩士
大葉大學
電機工程學系
100
This thesis presents a new balanced microstrip-fed loop printed antenna, using in the WLAN band (2.4 GHz - 2.484 GHz). This antenna uses a slot to rectifier the return current on the metal antenna, becoming a non-symmetric antenna. Further we use a non-symmetric structure to make the symmetry in the current distribution for overcoming the common-mode reflection. Compared with single-ended and balanced-fed of the microstrip-fed loop antenna, it has a smaller area. In addition, using balanced transmission-line is better than using unbalanced transmission-line to resist noise interference. In this thesis, we use full-wave simulation to design and produce the antenna prototype, and prove its performance according to experimental results.