<p>Godkänd; 1991; 20080410 (ysko)</p>

The Transmission Line Modelling (TLM) method is applied to the electromagnetic modelling of vehicles. Implications of increasing frequencies in computer models of electromagnetic compatibility (EMC) studies are discussed. Efficient algorithms and resource management strategies are developed With a view to producing accurate results m a realistic computational run time. Theoretical aspects covered are: (1) the development and accuracy of the TLM method; (2) an improved Partial Huygens' surface for plane wave excitation; (3) an evaluation of high-performance local and global absorbing boundary conditions. Implementation aspects of TLM addressed include: (1) the effects of arithmetic precision on link line voltage and stub impedance calculations; (2) the development of an object-oriented computer code using the Object Modelling Technique; (3) methods for estimating and managing the memory requirement and run lime of simulations. It is shown that by optimizing algorithms and carefully managing resources, sufficient improvement can be made to allow relatively sophisticated models to be run on a modest desktop computer.

This article addresses over the regulation of the surface right in the Peruvian Law along with its main points of contact with other important institutions in the field of real estate. The author points the evolution of this figure in the Peruvian legislation and determinates its legal nature and its characteristics, establishing its relation with the principle of real estate accession property and the implications of the transitional division that the surface generates. In other relevant aspects, the article addresses the ways of acquisition of such ownership, the role of inscription in the configuration of the surface, the reimbursement of the value of the buildings and the extinction of this property right. / Este artículo trata sobre la regulación del derecho real de superficie en el Derecho peruano y sus principales puntos de contacto con otras importantes instituciones en el ámbito inmobiliario. El autor aborda la evolución de dicha figura en la legislación peruana y determina la naturaleza jurídica y características del referido derecho, estableciendo su relación con el principio de accesión inmobiliaria y las implicancias de la división transitoria predial que genera la superficie. En otros aspectos relevantes, en este artículo se desarrollan las formas de adquisición de dicha titularidad, el papel de la inscripción en la configuración de la superficie, el reembolso del valor de las edificaciones y la extinción de este derecho real.

The aims of this project were to investigate the effect of immune complexes on mononuclear phagocytes in the presence or absence of infection with the human immunodeficiency virus (HIV). Mono Mac 6 (MM6) cells and human monocyte-derived macrophages (MDM) were used to compare the effect of chemical stimulants, cytokines and immune complexes on surface antigen expression. The same experiments were performed using HIV-infected cells to determine the effect of HIV infection on these parameters. Some of the stimulants especially IL-6, IL-10, TNF-alpha and HIV increased CD80 expressions, the effect being greater in MDM than MM6 cells. This has implications for antigen presentation. Cytokines caused the differentiation of MM6 cells and significantly increased or decreased surface antigen expressions. The MM6 cells express surface antigens at lower levels then MDM this indicates that MM6 cells need to differentiate before expressing surface antigens. The high standard deviations obtained meant that no significant change in surface antigen expression was seen in all HIV non-infected and infected MDM incubated with various immune complexes and HIV-sera. Comparing whole blood incubated with KLH and rabbit anti-human IgG showed that both seemed to produce IL-10 and IL-6 early. Only rabbit complexes stimulated TNF-a release. MDM incubated with IL-6, IL-10, and TNF-alpha showed increased expression of CD16 and CD80 only at day 3. However, HIV proteins (CHO) incubated in whole blood caused a significantly release of IL-6 at 8 hours with no detection of IL-10 and TNF-alpha. MM6 infected with HIV-1 Ba-L for 5 days showed increased expression of CD16 and CD11c, but reduced expression of the other antigens examined. Significant levels of IL-10 were released at 8 and 12 hours with a slight increase in IL-6, and TNF-alpha. HIV protein-containing (CHO) immune complexes slightly increased IL-6 secretion at 8 hours at which point, IL-10 production was high. HIV- infected cells incubated with HlV-sera showed a lack of TNF-alpha release but IL-6 and IL-10 was detected at 12 and 8 hours respectively. The detection of high levels of IL-10 and the inhibition of TNF-alpha production may stimulate progression to full blown AIDS.

La bio-détection de molécules reposant sur le phénomène de résonnance plasmon permet de détecter des espèces en utilisant les propriétés optiques de films métalliques. L’utilisation de ce type de capteurs nécessite néanmoins l’augmentation de leurs performances afin de détecter des concentrations faibles d’analyte dans des milieux complexes. L’assemblage de nanoparticules d’oxyde de fer sur des substrats d’or, en utilisant des groupements complémentaires spécifiques via la méthode de chimie « click », permet de contrôler leur distribution spatiale à la surface du substrat. Les propriétés magnétiques portées par les nanoparticules sont ainsi étudiées en fonction de leurs distances inter-particules ainsi que de leurs tailles. Par ailleurs, le plasmon de surface du substrat étant directement influencé par l’assemblage des nanoparticules, il sera possible de contrôler la sensibilité du capteur pour étudier la détection de différentes biomolécules impliquées dans des processus biologiques. La présence des nanoparticules augmente les propriétés optiques intrinsèques de la surface du substrat et la géométrie de l’assemblage permet d’augmenter la quantité de biomolécules détectées. / Biomolecular detection based on the surface plasmon resonance phenomenon allow detecting species by using the optics properties of metallic thin films. This kind of biosensors require the increase of their performances in order to detect low concentration analyte in complex medium. The assembly of iron oxide nanoparticles on gold substrates by using specific complementary groups via the “click” chemistry technique allows controlling their spatial distribution on the substrate surface. The magnetic properties carried by the nanoparticles are studied as function of their inter-particle distances and their sizes. Moreover, the surface plasmon of the substrate is directly influenced by the nanoparticle assembly and the control of the sensor sensitivity will be possible in order to study the detection of different biomolecules implies in biological processes. The presence of nanoparticles increases the intrinsic optical properties at the substrate surface and the geometry of the assembly allow increasing the number of biomolecules detected.

Agricultural runoff is a major non-point source pollutant in the Midwest and has been documented as a significant contributor to nutrient loads in the Mississippi River and subsequent hypoxic conditions in the Gulf of Mexico. In an attempt to minimize eutrophication, researchers have been collaborating with farmers to improve best management practices targeting nutrient retention. Over the past four decades riparian buffers have proven effective in retaining nutrients and sediment from agricultural runoff. We hypothesize that the addition of biochar to vegetated buffers can further improve nutrient attenuation by enhancing nutrient adsorption and cycling soil physical, chemical, and biological properties. In June 2012, fifteen flumes were established adjacent to fifteen existing flumes that were installed in 2008 for a related study at Southern Illinois University's farms. Each flume was either vegetated and/or amended with one of ten treatments and replicated three times: 1) giant cane (Arundinaria gigantea (Walt.) Muhl) established in 2008; 2) Kentucky bluegrass (Poa pratensis L.); 3) orchardgrass (Dactylis glomerata L.); 4) giant cane and compost (i.e., horse manure and mushroom compost); 5) biochar (i.e., pine and oak feedstock pyrolyzed between 450 °C and 650 °C.); 6) biochar and giant cane; 7) biochar, giant cane, and compost; 8) corn; 9) volunteer herbaceous species; and 10) a non-amended, non-vegetated control. Soil samples were collected prior to the application of soil amendments and nutrients were assessed annually. Surface runoff samples were collected from significant rain events (i.e., precipitation > 2.5 cm) and analyzed for nutrient and sediment levels. Data indicate that various combinations of biochar, compost, and giant cane were successful at reducing the frequency of surface runoff events as well as reducing concentrations of NO3- and NH4+ in agricultural surface runoff. Concentrations of dissolved reactive phosphorus (DRP) were greatly reduced when biochar and giant cane were present in the buffer without the addition of compost. Total phosphorus (TP) concentrations were lowest for the established giant cane treatment. There were no significant differences in the concentrations of total suspended solids (TSS) among the various buffer treatments. Data from this study are promising for the incorporation of biochar, compost, and giant cane into vegetated buffers to reduce the concentration of nutrients in agricultural surface runoff.

The grassland bird-community has declined significantly in abundance and diversity in Illinois over the past century. Reclamation of surface coal-mines in southern Illinois has created ca. 50,000 ha of grassland habitat that offers surrogate habitat for grassland and shrubland birds. Much of the grassland habitat created by reclamation of mine lands has not been managed and has succeeded to shrubland habitat dominated by both native and non-native shrubs. The purposes of this research were to identify the bird community utilizing reclaimed surface-mines in southern Illinois, and to examine the habitat-associations of the bird community and compare those to previously reported habitat-associations. I examined bird communities, plant structure and composition, and invertebrate communities at grasslands and shrublands at 3 reclaimed surface-mines in southern Illinois. I used 100-m wide strip-transects to survey the bird community and measured habitat characteristics including: vegetation height and density, litter depth and cover, shrub density and height, and plant composition. I observed 57 bird species over 126 surveys in 2008 and 2009. I used Generalized Linear Models and Akaike's Information Criteria to develop habitat-association models for 7 bird species: Henslow's sparrow (Ammodramus henslowii), grasshopper sparrow (Ammodramus savannarum), eastern meadowlark (Sturnella magna), dickcissel (Spiza americana), indigo bunting (Passerina cyanea), field sparrow (Spizella pusilla), and Bell's vireo (Vireo belli). Of these 7 species, dependable models were found for the Henslow's sparrow, grasshopper sparrow, eastern meadowlark, and field sparrow. The best habitat model for Henslow's sparrows indicated a positive association with % litter cover and a negative association with large variations in grass cover. The best habitat model for grasshopper sparrows indicated a negative association with both litter cover and depth and a positive association with grassland area. The best habitat model for the eastern meadowlark indicated a negative association with visual obstruction and shrub density. The best habitat model for the field sparrow indicated a curvilinear association with shrub density and visual obstruction. The habitat-association model for Henslow's sparrows differed from previous research in that neither vegetation height nor density were indicated as important habitat characteristics. To identify the habitat characteristics that have the greatest effect on the overall bird-community composition, I generated graphical ordinations using non-metric multidimensional scaling. The habitat factors most affecting the bird community composition were: vegetation density, vegetation height, litter depth, shrub density, shrub height, warm-season grass cover, and the ratio of habitat area to perimeter. Invertebrate biomass at a site was positively correlated to forb cover and plant richness and negatively correlated to grass cover. Grassland bird species have distinct habitat-associations that allow them to reduce interspecific competition through niche partitioning and would be best managed with a diverse set of successional stages.

Implementing effective and environmentally responsible carbon capture technologies is one of the principle challenges of this century. Successful implementation requires a host of engineering advancements, but also a fundamental understanding of the underlying physics, chemistry, and materials science at play in these highly complex systems. A large body of scholarship examines both current technologies as well as future strategies, but to date little exploration of the surface behavior of these systems has been examined. As these carbon capture systems involve uptake of gaseous CO2 to either aqueous or solid substrates, understanding the chemistry and physics governing the boundary between the two reactant phases is critical. Yet probing the unique chemistry and physics of these interfacial systems is very difficult. This dissertation addresses this knowledge gap by examining the surface chemistry of monoethanolamine and CO2. Monoethanolamine is a simple organic amine currently used in small scale CO2 scrubbing, and acts as an industrial benchmark for CO2 capture efficiency. The studies presented throughout this dissertation employ surface selective techniques, including vibrational sum frequency spectroscopy, surface tensiometry, and computation methodologies, in order to determine the behavior governing aqueous amine interfaces. The adsorption behavior and surface orientation of aqueous monoethanolamine is examined first. The results show monoethanolamine is present at the surface, highly ordered, and solvated. Perturbations to this amine surface from gaseous CO2 and SO2, as well as from liquid HCl, are examined in the remainder of the dissertation. Reactions between the amine and acids are shown to cause immediate changes to the interface, but the interface then remains largely unaffected as further reaction evolves. The studies presented herein provide a needed exploration of the interfacial picture of these highly reactive systems, with implications for future carbon capture materials and design.

Les structures composites sont de plus en plus présentes dans le domaine aéronautique. Le perçage, procédé qui permet le montage de fixations pour assembler ces structures, peut induire des défauts tels que délaminages, écaillages, arrachements de fibres ou surchauffes au niveau de l’alésage.Dans la littérature les auteurs s’intéressent principalement aux défauts créés en entrée et en sortie de trou. Aussi, cette recherche s’est focalisée sur les défauts de paroi crées par l’opération de perçage. Une caractérisation qualitative et quantitative a été proposée et le lien entre ces défauts et la tenue mécanique a été évalué.L’état de surface des parois est quantifié via sa rugosité qui mesure globalement les défauts générés lors du perçage. Jusqu’à présent, la qualité de la surface est estimée par un critère de rugosité géométrique Ra issu de la culture métallique. Il présente un certain nombre d’incohérences pour les perçages des composites. Dans ce travail de thèse, les relations entre les paramètres de perçage, le matériau de l’outil, sa géométrie et la qualité des alésages mesurée par les critères normalisés d’état de surface ont été établies. Un critère de qualité des parois de trou pour les matériaux composites autre que les critères normalisés a été proposé.La nature intime de la surface de contact influence clairement la qualité du transfert de charge par contact localisé. Dans un premier temps, l’influence des défauts de paroi sur la tenue en matage quasi-statique a été établie, ensuite, la tenue en compression quasi-statique des stratifiés C/E liée à la présence de défauts de paroi a été étudiée. Une analyse de la tenue en fatigue des stratifiés percés liée à la présence des défauts d’état de surface a aussi été réalisée. Enfin, une analyse numérique originale par éléments finis incluant une représentation géométrique des défauts observés, a permis de mieux cerner la cinétique d’endommagement des stratifiés percés liés à la présence de défauts de paroi / Composite materials are finding an increasing number of applications in the aerospace industry. The drilling is the process that allows the fasteners installation. The drilling operation can induce defects such as delamination, fibers and matrix pull-out and matrix burning.Previous studies focused mainly on the defects created at the hole entry and exit. Only few of these studies concern the hole wall drilling defects. In this study, we focused on the hole wall defects created by the drilling operation. A qualitative and quantitative characterization of defects was proposed and the relationship between these defects and the mechanical strength was evaluated.The hole surface finish is quantified by the roughness criterion Ra, that comes from metallic culture. Because of their heterogeneous nature, composite materials do not present the same defects patterns as metallic materials. The question that arises is whether the roughness may have an influence on the mechanical behavior of composite materials. In this study, the relation between the drilling parameters, the drill material, its geometry and the hole quality quantified with normalized parameters has been established. A criterion used to quantify the hole surface finish of composites have been proposed.The inner nature of the contact surface clearly influences the load transfer quality. As a first step, the influence of the hole wall defects on the quasi-static bearing behavior has been established, then the compressive behavior linked to the presence of hole wall defects have been studied. An analysis of the fatigue behavior of drilled laminates due to the presence of hole wall defects have been conducted.Finally, a numerical analysis by finite elements including an original geometric representation of the defects observed, has allowed to further clarify the damage kinetics of drilled laminates linked to the presence of drilling defects.

Dans les travaux de recherche développés durant cette thèse, une première approche desécoulements magnétohydrodynamiques (MHD) multiphasiques est proposée. Cette approche seconcentre sur les phénomènes liés à l’interaction entre une dynamique interfaciale et un écoulementde coeur MHD. Le couplage induit entre rhéologie de surface etMHDde sous-phase est particulièrementillustré par le développement d’un viscosimètre annulaire surfacique, dédié à l’étude desmétaux liquides progressivement oxydés. En premier lieu sont introduits les éléments théoriquespropres à laMHDet à la rhéologie de surface. La modélisation de leur couplage fait intervenir deuxparamètres interfaciaux : les viscosités surfaciques dilatationnelle et de cisaillement. L’influence respectivede ces deux paramètres sur l’écoulement MHD de sous-phase est étudiée analytiquementet numériquement dans le cas d’un écoulement (stratifié) annulaire MHD permanent. Dans la configurationretenue, un champ magnétique uniforme vertical est imposé, perpendiculairement à lasurface liquide graduellement oxydée. Le rôle décisif des contraintes visqueuses interfaciales concernantl’(in)activation des couches de Hartmann est démontré, conduisant à des topologies atypiquesd’écoulement MHD. Le viscosimètre annulaire MHD est ensuite proposé en tant que méthodeexpérimentale originale, permettant la mesure sélective des viscosités surfaciques de fluides électroconducteurs.Les premières campagnes expérimentales aboutissent à une estimation de la viscositéde cisaillement interfacial d’un alliage métallique (GaInSn) liquide à température ambiante. Finalement,une ouverture sur l’écoulement MHD à proximité d’une inclusion gazeuse sphérique rigideest discutée en annexe de ce projet, en lien avec des conditions mécaniques variables à l’interfaceliquide/gaz pilotées par la rhéologie de surface, constituant une première approche vers la descriptiondes écoulements MHD dispersés. / In this thesis work, a first approach towards the description of magnetohydrodynamic(MHD) multiphase flows is proposed, based on the investigation of the role of surface rheologyin permanent regime. The study of the coupling between bulk MHD and surface rheology is particularlymotivated by the development of an annular surface viscometer devoted to liquid metalstopped with an oxidation layer. First, theoretical foundations of MHD and of surface rheologyare separately introduced. The modelling brings out a strong coupling between bulk and surfacevelocities, the latter being dependent on two interfacial parameters: the surface shear and dilatationalviscosities. Their respective influence is analytically and numerically investigated in the caseof a permanent annular (stratified) MHD end-driven flow. In the considered geometry, a vertical(uniform) magnetic field is imposed, perpendicular to the gradually oxidising liquid surface. Thecontribution of planar surface viscous stresses to the possible electrical activation of Hartmannlayers is demonstrated, leading to a variety of atypical MHD flow patterns. The annular MHDviscometer is then developed as a first device able to perform selective measurement of the surfaceviscosities of electroconductive fluids. First experiments lead to an estimated value of the surfaceshear viscosity for a liquid alloy (GaInSn) at room temperature. Some hints are finally given to investigatethe study case of aMHDflow past a rigid fluid sphere, with varying interfacial conditionsgoverned by surface rheology, as an additionalwork constituting a first step towards the descriptionof dispersed MHD flows.