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Scheffler, Michael. "Cost vs. quality trade-off for high-density packaging of electronic systems /". Zürich, 2001. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=14210.
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LeBlanc, Denis R. "Density and recharge effects during the Cape Cod natural-gradient tracer test". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/84242.
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Goss, Cullen. "SLM 125 Single Track and Density Cube Characterization for 316L Stainless Steel". DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2050.
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Selective Laser Melting is a rapidly developing additive manufacturing technique that can be used to create unique metal parts with tailormade properties not possible using traditional manufacturing. To understand the process from a most basic level, this study investigates system capabilities when melting single tracks of material. Individual tracks allow for a wide range of scan speeds and laser powers to be utilized and the melt pools analyzed. I discuss how existing studies and simulations can be used to narrow down the selection of potentially successful parameter combinations as well as the limitations of interpretation for single track information. Once we attain a solid understanding of what parameters perform well at a bead level, we can move onto looking at complete 3D parts. A challenge we have faced is creating near fully dense parts and determining a reliable density measurement technique that is accessible for operators at our university. Our results show that the previously determined optimized scan speed and laser power can consistently create parts with >99.5% density over a range of sizes using an analysis method utilizing readily available equipment and software.
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Houser, AnnMarie. "Spoor density, movement and rehabilitation of cheetahs in Botswana". Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/27083.
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The “vulnerable” listing by IUCN of cheetah Acinonyx jubatus in Africa has caused urgency in the protection of their habitat and development of predator management strategies. By understanding the movement and home range of cheetah in Botswana, translocation of problem cheetah or reintroduction of non-problem animals can be managed appropriately. More importantly this information will help to protect what is already there. Due to the increasing numbers of cheetahs being taken by illegal trade and poaching, there have become incidents of orphaned cubs where the only option for their survival is rehabilitation for release into the wild, or euthanasia. The first part of the study focuses on baseline information of movement patterns of cheetah in Botswana. Eleven cheetahs were collared and monitored from 2003-2007, including males and females with and without cubs from the Ghanzi and Southern districts. The understanding of cheetah movement is critical in determining methods of protection and survival of the species in protected areas living with competing predators such as lion Panthera leo, brown hyaena Hyaena brunnea and leopard Panthera pardus, as well as on farmlands where human conflict and habitat loss are the main causes of cheetah death. In the Southern district the cheetah were able to move freely in and out of the Jwana Game Reserve surrounded by communal livestock farms with low to medium conflict, utilizing various livestock protection methods, whilst Ghanzi consisted of livestock and game farms where conflict was high and protection methods were limited or nonexistent. Home ranges in males ranged from 492 km2(in single males) to 849 km2(in one coalition) in Ghanzi, while females ranged from 241 km2 to 306 km2 in Jwaneng. In addition, in order to determine the correlation between spoor density and true density, a 15 month spoor study was conducted in Jwaneng at the Jwana Game Reserve on a population of free ranging wild cheetah. A correction factor was tested and adjusted for accuracy, resulting in two formulas to be used in the wet and dry seasons. Spoor surveys are by no means a determinant factor, as they need to be repeated over time to observe population fluctuations due to outside factors, and are time consuming and can be expensive, but they are a management tool that can be utilized for estimations of cheetah densities on private farms or protected areas. The third part to the study was the rehabilitation of three orphaned cubs, from different families, that were put together from eight to twelve weeks old. The goal of this project was to raise and release fully functional, self sufficient, breeding animals into the wild population on a game farm. These cubs were raised in isolation until 1.5 years of age, then transferred to a 100 ha enclosure where they were given the opportunity to learn to hunt. Daily observations of their behavioural development and hunting abilities were recorded for 48 days and are presented in a descriptive way. At two years old they were released onto a 9000 ha game farm where their potential to survive on farmland was monitored. Botswana does not have the facilities or desire to keep predators captive, and if orphaned cubs could be utilized by placing them back into wild populations where they could add to the gene pool, alternatives would be available for captive bred animals or cheetahs facing life long captivity. CopyrightDissertation (MSc)--University of Pretoria, 2009.
Centre for Wildlife Management
unrestricted
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Underdown, Robert Kyle. "Declining trade union density and the future of the Union Movement in Australia /". Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09AR/09aru55.pdf.
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Ahmad, Hafiz Bashir. "Intraspecific variability in embolism resistance and functional trade-offs in sunflower (Helianthus annuus L.) and Maritime pine (Pinus pinaster Ait.)". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0747/document.
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Plusieurs études ont montré que la productivité des forêts et des cultures décroît sur l’ensemble de la planète en réponse au changement climatique, et que les risques de mortalité liée à la sécheresse s’accroissent. Ces mortalités massives ont été observées dans tous les écosystèmes forestiers et seraient dues à un dysfonctionnement hydraulique des plantes, causé par de l’embolie xylémiène. Le spectre interspécifique de résistance à l'embolie a été largement étudiée, mais peu d'attention a été accordée à la variabilité intra-spécifique de ce trait. C’est pourquoi, l’objectif de ce travail de thèse était d’améliorer notre compréhension de la variabilité intra-spécifique de la résistance à l’embolie chez une espèce cultivée(Helianthus annuus L.) et chez un conifère (Pinus pinaster). Nous avons déterminé la vulnérabilité à l’embolie de quatre variétés de tournesol, présentant des différences significatives de P50 (pression induisant 50% de perte de conductivité hydraulique), allant de -2.67 à -3.22 MPa. Un compromis entre sécurité hydraulique et croissance a été observé mais pas entre la sécurité hydraulique et la capacité de transport de l'eau du xylème. Seuls quelques caractères anatomiques, tels que la densité des vaisseaux et la surface du lumen, présentent une corrélation avec la résistance à l’embolie. Dans un second temps, nous avons phénotypé pour la résistance à l’embolie et la densité du bois 477 génotypes de P. pinaster, issus d’une F2 de pleins-frères correspondant à la 3ème génération consanguine obtenue par auto-fécondation d’un hybride inter-provenance “Corse × Landes. La variabilité de la P50 au sein de l’espèce était extrêmement faible (CVP=5.6%). D’autre part, nous avons mis en évidence l’absence de compromis entre sécurité hydraulique et densité du bois. La part de variance du caractère P50 expliquée par QTLs (PEV)correspondait à 23.6% de la variance phénotypique totale mais aucun QTL commun n’a pu être détecté entre P50 et densité du bois, suggérant qu’au sein de cette famille, la plus forte résistance à l’embolie de certains génotypes n’est pas liée à un bois plus dense. Une analyse multi-caractère du fonctionnement de la feuille et du xylème a été réalisée via l’étude de la dynamique saisonnière de la fluorescence du photosystème II et des traits hydrauliques de la tige, sur une famille de pleins-frères d’un hybride interprovenance “Maroc × Landes” de P. pinaster ; en réponse à une diminution du potentiel hydrique,l’efficience du photosystème II et la conductance stomatique ont tous deux diminué, induisant une décroissance rapide du taux d’assimilation. La résistance à l’embolie du xylème n’a pas montré de relation significative avec les traits foliaires. L’absence de compromis entre ces caractères permet donc d’envisager la sélection génétique de génotypes à la fois efficients et résistantsAs a consequence of current global climate change, forest and crop ecosystems are decreasing inproductivity worldwide and are under increased threat of widespread drought-induced mortality due tohydraulic failure caused by xylem embolism. The range of embolism resistance across species has been intensively studied but little attention has been paid to intraspecific variability. This thesis aimed thereforeat improving our understanding of the intraspecific variation in embolism resistance in one crop species(Helianthus annuus L.) and one conifer species (Pinus pinaster). In the first place, vulnerability to embolism was determined across four sunflower accessions with significant variations in P50 (pressure inducing 50% loss of hydraulic conductivity) ranging between -2.67 and -3.22 MPa. A trade-off between hydraulic safety and growth was observed but not between hydraulic safety and efficiency. Only few anatomical traits, such as vessel density and vessel lumen area, were found related to embolism resistance.Secondly, we phenotyped 477 P. pinaster full-sib F2 genotypes corresponding to a three-generation inbred pedigree obtained by the self-pollination of an inter “Corsica × Landes” provenance hybrid, for embolismresistance and wood density. The variability for P50 within species was remarkably low (CVP=5.6%). Wealso found a lack of trade-off between hydraulic safety and wood density. The phenotypic variance explained by QTLs (PEV) detected for P50 accounted for 23.6% of the phenotypic variation but no QTL collocated between P50 and wood density, suggesting that embolism resistant genotypes in this family are not dependent on denser wood. A multi-trait analysis of leaf and xylem functioning was performed through seasonal measurements of photosystem II fluorescence and stem hydraulic traits on a full-sib family of aninter “Morocco × Landes” provenance hybrid of P. pinaster; it revealed that with decreasing water potential, the efficiency of both photosystem II and stomatal conductance decreased which resulted in rapid decrease in assimilation rate. Xylem resistance to embolism was found having no relationship with leaf functioning traits. The absence of trade-off between these traits makes it possible to consider selection for both efficient and resistant genotypes
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KAYITESI, Aline. "TRADE UNIONS AND UNEMPLOYMENT : ASSESSMENT OF THE CROSS-COUNTRY EVIDENCE". Thesis, Linnéuniversitetet, Institutionen för nationalekonomi och statistik (NS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-104581.
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The aim of this thesis is to examine the relationship between union’s indicators namely union density rate and collective bargaining coverage rate, and the unemployment rate. I have conducted an empirical analysis on 34 OECD countries grouped into three groups based on their bargaining systems. The results indicate that there is no linear relationship between union density and collective bargaining coverage, and the unemployment rate in countries which have centralized co-ordinated, organized decentralized but co-ordinated bargaining systems and that those systems do not have influence on the way unions affect unemployment rate. However, the predominatly centralized but weakly co-ordinated system indicates to have a positive effect on the way unions affect unemployment rate and union density /collective bargaining coverage are positively related with the unemployment rate in this group. I try to argue for possible reasons for these findings.
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Zhang, Jin 1960. "The influence of copper deficiency on the binding and uptake of high-density lipoprotein by rat hepatic parenchymal cells". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276935.
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This study was designed to examine the influence of Cu deficiency on the binding, uptake, and degradation of apolipoprotein E-free high density lipoproteins (apo E-free HDL) in cultured rat hepatic parenchymal cells. The binding of apo E-free HDL during time course studies was slightly but significantly increased in cells derived from Cu-deficient rats. In saturation studies, the amount of surface-bound apo E-free HDL appeared to be saturable, although no difference was observed between Cu-deficient and adequate animals. The amount of total and specific cell-associated uptake of apo E-free HDL was significantly increased in hepatic parenchymal cells of Cu-deficient animals. The present data suggest that hepatic uptake of the HDL protein moiety may be increased in rats fed a diet deficient in copper.
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Sabil, Naïma. "La datation par les traces de fission : aspects méthodologiques et applications thermochronologiques en contexte alpin et marge continentale". Phd thesis, Grenoble 1, 1995. http://www.theses.fr/1995GRE10066.
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La méthode de datation par les traces de fission de l'uranium s'est révélée unique dans le domaine de la thermochronologie par sa capacité à retracer l'histoire finale du refroidissement et de la dénudation de massifs métamorphiques comme de l'histoire thermique de formations sédimentaires ou la datation de certains matériels volcaniques. Dans ce travail, nous décrivons cette méthode et présentons un ensemble de techniques analytiques mises au point et de calibrations réalisées dans le but d'utilisations ultérieures en géologie. Nous discutons quelques exemples d'application. Dans les Alpes occidentales françaises, l'analyse des traces de fission sur apatites d'échantillons issus du granite des Sept Laux (massif de Belledonne), dans la vallée de l'Eau d'Olle, suggère que cette méthode pourrait apporter une contribution dans la discussion actuelle sur l'origine de certaines vallées alpines. Ainsi, l'ouverture de cette vallée pourrait être la conséquence d'un jeu de failles actives depuis le Miocène moyen jusqu'à l'actuel. La caractérisation par traces de fission des apatites détritiques de dépôts fluviaux pourrait éventuellement être utilisée pour l'étude d'éventuels phénomènes de captures liées à des changements de régimes tectoniques. Nous avons ainsi étudié les apatites d'un paléodelta situé dans la moyenne vallée de l'Isère au niveau du sillon subalpin, et de deux vallées, celles de l'Arc et du Bréda, situées en amont. La distribution des âges traces de fission de ces minéraux n'a pas confirmé un modèle suggéré récemment, qui proposait que le paléodelta étudié pourrait être associé à un «paléo-Arc» plutôt qu'à un «paléo-Bréda». Dans la Meseta occidentale marocaine, trois massifs granitiques (massif de Sebt Brikiine, de Ras El Abiod et de Hjir El Bark) situés dans les Rehamna ont fait l'objet d'une étude thermochronologique. L'analyse des traces de fission dans les zircons et les apatites de ces granites montre qu'ils ont enregistré les grands évènements thermotectoniques ayant affecté la Meseta depuis l'ouverture de l'Océan Atlantique central. Nous montrons comment un modèle de simulation numérique récemment proposé (1994) pour l'analyse des traces de fission dans les apatites permet de préciser l'histoire thermique des massifs considérés depuis le dernier refroidissement au-dessous d'environ 120°C des échantillons analysés. Dans des travaux effectués antérieurement à l'apparition de ce modèle, nous avons montré, d'une part, que les sédiments de la marge transformante de Côte d'Ivoire-Ghana avaient connu une période de réchauffement entre 250°C et moins de 60°C post-datant largement, de manière inattendue, le «balayage» d'une dorsale océanique. D'autre part, dans l'Ile d'Elbe, nous avons apporté les premières données «traces de fission» sur l'histoire de refroidissement de la granodiorite de Monte Capanne. Par ailleurs, au début des années 90, la méthode des traces de fission manquait encore de bons échantillons de référence pour la datation des verres volcaniques. A la suggestion de la Sous-Commission de Géochronologie de l'International Union of Geological Sciences, nous avons étudié les macusanites, obsidiennes du SE péruvien. Les résultats de ce travail suggèrent qu'il faut considérer avec réserve ces verres volcaniques en tant que standards d'âge potentiels, même s'ils conservent une certaine valeur comme matériel d'intercalibration entre laboratoires
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Decker, Jeramy Bruyn. "Building, Updating and Verifying Fracture Models in Real Time for Hard Rock Tunneling". Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27220.
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Fractures and fracture networks govern the mechanical and fluid flow behavior of rock masses. Tunneling and other rock mechanics applications therefore require the characterization of rock fractures based on geological data. Field investigations produce only a limited amount of data from boreholes, outcrops, cut slopes, and geophysical surveys. In tunneling, the process of excavation creates a priceless opportunity to gather more data during construction. Typically, however, these data are not utilized due to the impedance of sampling and analysis on the flow of construction, and safety concerns with sampling within unlined tunnel sections. However, the use of this additional data would increase the overall safety, quality, and cost savings of tunneling.
This study deals with several aspects of the above, with the goal of creating methods and tools to allow engineers and geologists to gather and analysis fracture data in tunnels without interrupting the excavation and without compromising safety. Distribution-independent trace density and mean trace length estimators are developed using principles of stereology. An optimization technique is developed utilizing Differential Evolution to infer fracture size and shape from trace data obtained on two or more nonparallel sampling planes. A method of producing nearly bias free empirical trace length CDF's is also introduced. These new methods and tools were validated using Monte Carlo simulations. A field study was conducted in an existing tunnel allowing the above methods and tools to be further validated and tested. A relational database was developed to aid in storage, retrieval, and analysis of field data. Fracture models were built and updated using fracture data from within the tunnel. Utilization of state of the art imaging techniques allowed for remote sampling and analysis, which were enhanced by the use of 3d visualization techniques.Ph. D.
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Clementz, Christine. "Obstructing unionisation among young workers : A qualitative study on individualistic attitudes and employer resistance towards unionism". Thesis, Stockholms universitet, Sociologiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-128056.
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Declining union density rates have been and continue to be an ongoing issue and worry around the world. In Sweden, union density remains high in comparison to other countries, although not an exception to the declining rates which have largely encompassed young workers. The objective of this study is to research two phenomena that have been identified as influences surrounding why young workers do not become unionised. The research questions are 1. Can individualistic attitudes be linked to the decline in union density among young workers, if so how? and 2. Can employer resistance towards trade unionism be linked to the decline in union density among young workers, if so how?.There are substantial amounts of quantitative research devoted to trying to understand the decline, which motivated writing a report with a qualitative approach. Focus was put on the thoughts and views of six young individuals who are all involved with three Swedish trade unions, HRF, Handels and Seko. The results of the study revealed that both individualistic attitudes and employer resistance can be linked to declining union density rates among youths. Individualistic attitudes were analysed alongside Allvin and Sverke’s theories on the ‘era of individualisation’, which includes declining preparedness to participate in collective movements, the belief in the efficacy of the self and autonomous attitudes towards institutions. Individualistic attitudes that were conferred in the interviews revolved around matters such as young workers not being able to identify themselves with trade unions and their officials. Employer resistance methods were discussed in line with, among others, Brulin’s theory on the work place as a political arena, where employers and trade unions battle for the loyalty of the employees. Resistance towards trade unions seem to appear in various forms and different methods are used in order to obstruct individuals from becoming or remaining unionised. This includes subtle threats and ostracism from managers and co-workers and unmotivated changes of rosters.
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Schwarzenberger, Fabian. "The Integrated Density of States for Operators on Groups". Doctoral thesis, Universitätsbibliothek Chemnitz, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-123241.
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This thesis is devoted to the study of operators on discrete structures. The operators are supposed to be self-adjoint and obey a certain translation invariance property. The discrete structures are given as Cayley graphs via finitely generated groups. Here, sofic groups and amenable groups are in the center of our considerations. Note that every finitely generated amenable group is sofic. We investigate the spectrum of a discrete self-adjoint operator by studying a sequence of finite dimensional analogues of these operators. In the setting of amenable groups we obtain these approximating operators by restricting the operator in question to finite subsets Qn , n ∈ N. These finite dimensional operators are self-adjoint and therefore admit a well-defined normalized eigenvalue counting function. The limit of the normalized eigenvalue counting functions when |Qn | → ∞ (if it exists) is called the integrated density of states (IDS). It is a distribution function of a probability measure encoding the distribution of the spectrum of the operator in question on the real axis.
In this thesis, we prove the existence of the IDS in various geometric settings and for different types of operators. The models we consider include deterministic as well as random situations. Depending on the specific setting, we prove existence of the IDS as a weak limit of distribution functions or even as a uniform limit. Moreover, in certain situations we are able to express the IDS via a semi-explicit formula using the trace of the spectral projection of the original operator. This is sometimes referred to as the validity of the Pastur-Shubin trace formula.
In the most general geometric setting we study, the operators are defined on Cayley graphs of sofic groups. Here we prove weak convergence of the eigenvalue counting functions and verify the validity of the Pastur-Shubin trace formula for random and non-random operators . These results apply to operators which not necessarily bounded or of finite hopping range. The methods are based on resolvent techniques.
This theory is established without having an ergodic theorem for sofic groups at hand. Note that ergodic theory is the usual tool used in the proof of convergence results of this type.
Specifying to operators on amenable groups we are able to prove stronger results. In the discrete case, we show that the IDS exists uniformly for a certain class of finite hopping range operators. This is obtained by using a Banach space-valued ergodic theorem. We show that this applies to eigenvalue counting functions, which implies their convergence with respect to the Banach space norm, in this case the supremum norm. Thus, the heart of this theory is the verification of the Banach space-valued ergodic theorem. Proceeding in two steps we first prove this result for so-called ST-amenable groups. Then, using results from the theory of ε-quasi tilings, we prove a version of the Banach space-valued ergodic theorem which is valid for all amenable groups.
Focusing on random operators on amenable groups, we prove uniform existence of the IDS without the assumption that the operator needs to be of finite hopping range or bounded. Moreover, we verify the Pastur-Shubin trace formula. Here we present different techniques. First we show uniform convergence of the normalized eigenvalue counting functions adapting the technique of the Banach space-valued ergodic theorem from the deterministic setting.
In a second approach we use weak convergence of the eigenvalue counting functions and additionally obtain control over the convergence at the jumps of the IDS. These ingredients are applied to verify uniform existence of the IDS.
In both situations we employ results from the theory of large deviations, in order to deal with long-range interactions.
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Forrest, Robyn Elizabeth. "Simulation models for estimating productivity and trade-offs in the data-limited fisheries of New South Wales, Australia". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/3417.
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Recent shifts towards ecosystem based fisheries management (EBFM) around the world have necessitated consideration of effects of fishing on a larger range of species than previously. Non-selective multispecies fisheries are particularly problematic for EBFM, as they can contribute to erosion of ecosystem structure. The trade-off between catch of productive commercial species and abundance of low-productivity species is unavoidable in most multispecies fisheries. A first step in evaluation of this trade-off is estimation of productivity of different species but this is often hampered by poor data.
This thesis develops techniques for estimating productivity for data-limited species and aims to help clarify EBFM policy objectives for the fisheries of New South Wales (NSW), Australia. It begins with development of an age-structured model parameterised in terms of optimal harvest rate, UMSY. UMSY is a measure of productivity, comparable among species and easily communicated to managers. It also represents a valid threshold for prevention of overfishing. The model is used to derive UMSY for 54 Atlantic fish stocks for which recruitment parameters had previously been estimated. In most cases, UMSY was strongly limited by the age at which fish were first caught. However, for some species, UMSY was more strongly constrained by life history attributes. The model was then applied to twelve species of Australian deepwater dogshark (Order Squaliformes), known to have been severely depleted by fishing. Results showed that the range of possible values of UMSY for these species is very low indeed. These findings enabled a preliminary stock assessment for three dogsharks (Centrophorus spp.) currently being considered for threatened species listing. Preliminary results suggest they have been overfished and that overfishing continues. Finally, an Ecopath with Ecosim ecosystem model, representing the 1976 NSW continental slope, is used to illustrate trade-offs in implementation of fishing policies under alternative policy objectives. Results are compared with those of a biogeochemical ecosystem model (Atlantis) of the same system, built by scientists from CSIRO. While there were large differences in model predictions for individual species, they gave similar results when ranking alternative fishing policies, suggesting that ecosystem models may be useful for exploring broad-scale strategic management options.
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Palm, Johanna. "There is power in a union : Trade union organization, union membership and union activity in Sweden". Doctoral thesis, Stockholms universitet, Sociologiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-145563.
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This thesis investigates what factors affect union organization and, to some degree, union activity in the face of declining union density in the majority of Western countries. Union structures have been changing in recent decades, not only in terms of declining membership but also because women and white-collar workers are becoming a more stable part of the membership base, whereas previously highly organized groups, such as blue-collar workers, are in decline. The point of departure for this thesis is that union density changes must be understood on several different levels. Thus, we must investigate changing union density in light of changing institutional settings, changing labour market structures and changing norms and values on the individual level. The thesis consists of three empirical studies investigating union density changes and union activity in Sweden, and an introductory chapter that develops the theoretical and empirical (historical) background. The empirical studies investigate: (1) whether and how the influence of various aspects of class and ideology on union organization have changed over time, (2) the effect of structural change on union density increase and decline, and(3) what factors influence different attitudes towards industrial action among Swedish employees. Results show that union density decline in Sweden since the mid-1990s cannot be explained by any forceful shifts in the labour market structure or individuals’ opinions and/or attitudes related to trade unions to any significant degree. Union density decline in Sweden is of a general nature. However, an increasing divergence in union density across various categories of employees, including, e.g., private-sector vs. public-sector employees, young vs. older employees, employees of foreign origin vs. employees of Swedish origin, and the atypically employed vs. employees with standardized employment, is observed. Moreover, previously strong predictors of union membership, including class identity, ideology, sector of employment and type of employment contract, are in decline, but they still influence union organization and attitudes towards industrial action.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted.
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Nicot, Jean-Philippe. "Inverse modeling of subsurface environmental partitioning tracer tests /". Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Spence, Victora. "Estimating groundwater discharge in the oligohaline ecotone of the Everglades using temperature as a tracer and variable-density groundwater models". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3361.
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Recent research suggests that brackish, marine-derived groundwater up-wells in the oligohaline ecotone of the coastal Everglades, bringing with it phosphorus to an otherwise phosphorus-poor environment. The purpose of this study is to estimate the rates and timing of the groundwater discharge by using variable-density groundwater models constructed, calibrated, and validated with field measurements of hydraulic head and surface and subsurface temperature. Modeled groundwater discharge rates ranged from 5.4E-04 mm/day in August to -1.3E-03 mm/day in June for Shark Slough and 4.8E-01 mm/day in June to -1.4E-01 mm/day in January for Taylor Slough, where positive values imply groundwater discharge and negative values imply groundwater recharge. These results indicate that groundwater discharge rates during the period of study were low and perhaps a negligible source of marine-derived phosphorous in the oligohaline ecotone of Shark Slough but much higher and perhaps significant source of marine-derived phosphorous in the oligohaline ecotone of Taylor Slough.
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Yang, Zijiang. "Investigation of Intruder and Bulk Particle Behaviours in Dense Granular Flows". Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28816.
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This thesis aims to investigate the kinematics and diffusive behaviours of dense granular materials. The interest in modelling granular kinematic properties has grown rapid in recent years, as researchers endeavour to establish comprehensive constitutive laws to describe the local and non-local rheology in dense granular materials. Discrete element modelling on dense granular flow has proven to be a powerful tool to obtain both discrete and continual properties in granular flow, yet experimental study on granular flow relies heavily on particle monitoring, typically with one or many different properties than other particles in granular bulk. Given the mechanism of dense granular flow was not fully understood, simply inferring granular bulk behaviour from a single intruder can cause discrepancy in the measured properties and actual properties of granular bulk. In order to investigate the relation between tracer and bulk particle, we first performed discrete element simulations by inputting tracers and bulk particles with different sizes, densities and under various flow speeds and tumbler size, and the kinematics of tracer and bulk particles will be compared and used to test the validity of existing scaling laws in dense granular flows in rotating tumbler, since such flow configuration has wide industrial applications. We also used a series of experimental measurements on granular kinematics obtained by X-ray radiography to cross-validate the results of our simulation. In general, the simulation and experiments revealed qualitatively several interesting tracer and bulk particle relations in terms of different kinematic properties, though quantification of such relation required more sophisticated numerical algorithms and rigorous experimental setup. This measurement method can be used to support researchers intended to experimentally study granular flow, by providing insights on relations on kinematic quantities, such as velocity, inertia, shear and granular diffusion, between intruders and bulk particles in dense polydisperse granular flow.
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Stein, Jennifer. "Juvenile Scleractinian Coral Density, Composition, and Influence on the Adult Coral Population in Southeast Florida". NSUWorks, 2012. http://nsuworks.nova.edu/occ_stuetd/173.
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The purpose of this study was to collect baseline data of juvenile scleractinian coral density, spatial variability, size variability, and species composition across the linear shore parallel hard bottom coral communities offshore Broward County, Florida. Adult coral population data was also collected and compared with that of the juvenile coral population to better understand the local coral demographics and potential factors that influence the population structure. The juvenile and adult coral data from the Broward County coral communities was then compared to a second study region 50 kilometers south to identify latitudinal changes in the coral population structure.
The results of this study found that the densities and the list of coral species observed within the Broward County study region did fall within the range of densities found in other studies completed along the southern portion of the Florida Reef Tract and the Caribbean. Despite having similar species richness to other Caribbean studies, there was an overwhelming dominance of only a few species. This was also found in the adult coral population in the Broward study region.
The densities of both the juvenile and adult coral populations were significantly positively correlated as well as their number of species observed across the sites in the Broward County study region. Additionally, the highly dominant species found in the juvenile population were in the adult population.
Despite increasing coral density and diversity with decreasing latitude found in other studies conducted along the Florida Reef Tract, the results from this study were not as clear. Density of corals and the number of coral species did increase from north to south on the Outer reef however there was a significant decrease in the depth of the sample sites. On the Pavement habitat the density of juvenile corals increased from north to south however the number of coral species did not increase. The density and number of species of adult corals did not increase on the Pavement habitat with decreasing latitude as well making the results unclear.
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Valette, Olivier. "Contribution à l"amélioration de la résolution double trace du détecteur à grand angle solide diogène". Paris 11, 1986. http://www.theses.fr/1986PA112239.
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L'équation d'état et les propriétés de la matière nucléaire dense suscitent toujours un vif intérêt théorique. L'étude expérimentale de ce problème peut se faire, en laboratoire, au moyen de collisions d'ions lourds relativistes. Le peu de sensibilité à l'équation d'état des mesures inclusives a conduit au développement de détecteurs à grand angle solide capables de mesurer simultanément plusieurs dizaines de particules, comme par exemple le détecteur Diogène installé à Saturne. La multiplicité admissible dans Diogène est actuellement limitée par sa résolution double trace. La nécessité de réaliser ces collisions avec des systèmes lourds et l’augmentation prochaine des performances du synchrotron Saturne ont motivé une étude pour améliorer cette caractéristique. L'électronique actuelle, à temps d'intégration fixe, étant principalement en cause, l'utilisation d'une électronique à échantillonnage a été envisagée. Une partie du détecteur a été équipée de cette électronique, en parallèle sur le système existant pour des tests comparatifs. Le choix technique s'est porté sur les dispositifs à transfert de charge (CCD) adaptés aux exigences du détecteur. Le volume d'information à traiter et les contraintes liées à l'application rapide de cette étude ont conduit à limiter l'échantillonnage à une fréquence de 50 MHz. Dans ces conditions, l’utilisation d'un algorithme simple permet d'améliorer la résolution double trace d’un facteur trois environ. Une technique particulière a dû être utilisée pour conserver une bonne résolution en localisation dans le plan transverse du détecteur. Cette méthode entraîne toutefois une certaine détérioration de la résolution longitudinale. En conséquence, l’équipement complet du détecteur semble nécessiter un échantillonnage 100 MHz. Cependant l'équipement actuel à 50 MHz constitue déjà une aide à la reconstruction des trajectoiresThe equation of state and the properties of dense nuclear matter are of considerable theoretical interest. The experimental study of such a problem can only be done in the laboratory with relativistic heavy ions collisions. Since inclusive measurements have proven to be rather insensitive to the equation of state, large solid angle detectors have been developed to measure most of the charged particles emitted in these collisions. Such a detector, Diogène, can only accept up to about 40 particles. This limitation comes from the double crack resolution of the detector. The interest for heavy colliding systems and the future improvement of the Saturn synchrotron showed the need for a change of the present electronics with a fixed integration time to a new sampling electronics. For comparative tests, such an electronics has been added to a small part of the detector, together with the existing system. Charge-coupled devices (CCD) which offer a large dynamic range have been selected for such a purpose. The sampling frequency has been limited to 50 MHz because of present data acquisition constraints. The use of a simple algorithm has led to an improvement of the double track resolution, by a factor of three. A specific technique has been used to keep a good localization in the transverse plane of the detector. It however has damaged somewhat the spatial resolution in the longitudinal direction. Therefore the whole detector equipment seems to require a 100 MHz sampling rate, although the present 50 MHz eco electronics can already be used to help trajectory reconstruction
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Iranpour-Mobarakeh, Mehran [Verfasser]. "Experimental and numerical Investigations of Tracer- and Density- dependent Transport in highly stochastic heterogeneous porous Media and Evaluation of transverse Macrodispersion / Mehran Iranpour-Mobarakeh". Kassel : Universitätsbibliothek Kassel, 2017. http://d-nb.info/1155423569/34.
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Iranpour, Mobarakeh Mehran [Verfasser]. "Experimental and numerical Investigations of Tracer- and Density- dependent Transport in highly stochastic heterogeneous porous Media and Evaluation of transverse Macrodispersion / Mehran Iranpour-Mobarakeh". Kassel : Universitätsbibliothek Kassel, 2017. http://d-nb.info/1155423569/34.
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Sirijarukul, Suksawat. "Elaboration de membranes à traces en poly(éthylènetéréphtalate) ayant un gradient linéaire de taille de pore et une porosité constante". Montpellier 2, 2007. http://www.theses.fr/2007MON20110.
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Nous avons fabriqué un nouveau type de membrane polymère à traces avec des gradients de taille de pore et de densité de pore le long de la membrane. Ces gradients sont fort bien contrôlés de façon indépendante et par des procédés très simples. Dans une première étape, un gradient de densité de pores est obtenu par un déplacement d'un film de poly(éthylènetéréphtalate) –PET- devant un faisceau d'ions lourds de flux variable. Dans une seconde étape, la taille de pore est contrôlée par le trempage progressif du film préalablement exposé aux ions lourds dans une solution de soude 2N à 50°C. La relation entre densité de pores et taille de pore en chaque point de la membrane est préalablement choisie : nous avons fabriqué des membranes ayant une porosité constante et un gradient linéaire de taille de pore. Des mesures de microscopie électronique à balayage ont permis de contrôler la formation d'un pore cylindrique à travers toute l'épaisseur (13 µm) du film de PET, après exposition à un rayonnement UV centré autour de 312 nm. Un modèle théorique a été proposé pour décrire le phénomène de filtration tangentielle dans un canal ayant une paroi constituée d'une telle membrane : le cas d'une perméabilité constante donne lieu à des expressions analytiques relativement simples, contrairement au cas de la porosité constante. Une cellule a été montée et caractérisée par des mesures électriques et hydrauliques. Le caractère hydrophobe de la membrane est atténué en milieu basique (NaOH 10-2N) par ionisation des groupes carboxyliques. Nous avons montré que la durée variable du traitement à la soude concentrée permettant d'obtenir le gradient de taille de pore n'induisait pas un gradient de mouillabilité du matériau à la condition que celui-ci ait été exposé préalablement au rayonnement UVA new type of polymer track-etch membrane was produced with a gradient of pore size and another gradient of pore density along the large dimension of the membrane. Those gradients are independently very well controlled and obtained by simple procedures. In a first step, the pore density gradient is created by displacing the poly(ethyleneterephthalate) –PET- film in front of a swift heavy ions beam of varying flux. In a second step, the pore size is controlled by dipping progressively the previously ion beam exposed film into an aqueous solution of 2N NaOH at 50°C. The relationship between both gradients at any position along the membrane is predetermined before preparation: we have chosen to maintain porosity constant with a linear gradient of pore size. Scanning electron microscopy measurements allowed verification of the existence of a cylindrical pore through the whole thickness (13 µm) of the PET film after exposure to UV light centred around 312 nm. A theoretical model has been proposed which describes tangential filtration in a channel where one wall is such a membrane: the case of constant permeability leads to relatively simple analytical expressions contrary to the case of constant porosity. One cell was built up and characterized by electrical and hydraulic measurements. The membrane hydrophobic character is attenuated at high pH (10-2N NaOH) by ionization of the carboxylic groups. We showed also that varying etching time to obtain a gradient of pore size did not induce a wettability gradient provided that the material was previously exposed to UV radiation
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Deeds, Neil Edward. "Development and evaluation of partitioning interwell tracer test technology for detection of non-aqueous phase liquids in fractured media /". Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Kitaura, Joyanes Francisco-Shu. "Cosmic cartography : bayesian reconstruction of the cosmological large-scale structure with ARGO an algorithm for the reconstruction of galaxy-traces over-densities". kostenfrei, 2007. http://edoc.ub.uni-muenchen.de/8120/.
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Madimenos, Felicia C. 1980. "Reproductive Trade-Offs in Skeletal Health and Physical Activity among the Indigenous Shuar of Ecuadorian Amazonia: A Life History Approach". Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/11977.
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xx, 229 p. : ill. (some col.)Reproductive effort is a central element of human biology and ecology. Particularly for females, reproduction is energetically demanding, with elevated metabolic costs during pregnancy and lactation, followed by high child care costs. To satisfy energetic needs, women can adopt various physiological and behavioral strategies. On a physiological level, the energetic requirements of offspring may be met by adjusting metabolic allocation and/or drawing on maternal bodily reserves. On a behavioral level, women may reduce energy expenditure and/or increase energy intake. This study examined reproductive trade-offs in activity and skeletal health among the indigenous Shuar forager-horticulturalists of Ecuadorian Amazonia and had two main objectives. First, this research examined trade-offs in energy use during female reproductive states and behavioral adjustments made by females and males to meet high reproductive demands. Second, this study investigated skeletal health profiles among Shuar, as well non-Shuar Colonos, to identify the relationships between female reproductive factors and skeletal health. Research was conducted among adults in four Morona-Santiago communities. Skeletal health was measured using calcaneal ultrasonometry, and physical activity was measured using accelerometry. Extensive information on sociodemographics and reproduction was assessed through structured interviews. Age-related declines in bone mineral density (BMD) were observed for Shuar and Colonos, while Shuar BMD was significantly higher than that of other populations. These results suggest that normative data from developed countries may reflect suboptimal bone density levels. Regarding reproductive effects on skeletal health, results indicate that earlier menarcheal age and greater stature are associated with better bone health in postmenopausal life. These conclusions suggest the importance of the timing of early developmental stages in establishing bone status in adulthood. Results demonstrate that physical activity levels were similar between pregnant/lactating (P/L) and other women. However, P/L women appear to compensate for elevated energetic demands by relying on a male partner who has increased his energy expenditure, suggesting greater participation in subsistence activities. Overall, this study demonstrates the importance of biocultural strategies among women to meet high reproductive costs. Further, it emphasizes the utility of a life history framework for identifying trade-offs in physiology and behavior. This dissertation contains previously published and unpublished co-authored material.
Committee in charge: Dr. J. Josh Snodgrass, Chair; Dr. Lawrence S. Sugiyama, Member; Dr. John Lukacs, Member; Dr. John Halliwell, Outside Member
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Waldman, Alanna D. "Spatial and temporal trends in the Xestospongia muta (giant barrel sponge) population on the Southeast Florida Reef Tract". Thesis, NSUWorks, 2019. https://nsuworks.nova.edu/occ_stuetd/514.
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Xestospongia muta, the giant barrel sponge, is a key component of coral reef benthic communities in Southeast Florida and the Caribbean. Xestospongia muta increases habitat complexity and stability, and filters large volumes of water, enhancing water quality and facilitating nutrient cycling. Therefore, it is important to investigate trends in the X. muta population on Southeast Florida reefs in response to anthropogenic stressors, changing environmental conditions and acute disturbances and how these events affect its ecological role in the benthic community. This study identified trends in X. muta population density, volume, and size class distribution over time and across reef habitats on the Southeast Florida Reef Tract (SEFRT). Density and volume changes were also investigated following acute physical disturbance caused by Hurricane Irma in September of 2017. Images and demographic data collected at 41 permanent sites from two long-term monitoring projects, The Southeast Florida Coral Reef Evaluation and Monitoring Project (SECREMP) and the Broward County Biological Monitoring Project (BC BIO), were used to evaluate the X. muta population trends. My analysis of the data from 2003 to 2018 shows that Xestospongia muta densities and volume increased over time regionally on the SEFRT and increased on the nearshore, middle, and outer reefs of the SEFRT. Xestospongia muta was found to be more abundant on the SEFRT compared to other locations including the Bahamas, the Florida Keys, Colombia, Belize and Saba. Highest mean density on the SEFRT was 0.35 individuals m-2 ±0.04 SEM, which was higher than the mean densities between 0.21 and 0.29 individuals m-2 at the Caribbean sites previously mentioned. Xestospongia muta individuals were categorized into size classes by volume to investigate density distribution of size classes on the SEFRT. Greater abundances in the smallest of five size classes (≤143.13 cm3) drove the increasing density trends. Despite the increasing trends from 2003 to 2017 with a peak in density and volume in 2017, Hurricane Irma caused a region-wide decline in population density and volume as well as a loss of individuals within the largest size class by volume (>17383.97 cm3). These results indicate that the X. muta population is exhibiting increasing long-term trends on the SEFRT, but also demonstrate that acute physical disturbances have a significant impact on the demographics of the population. Because of this sponge’s multiple roles in the reef communities, these trends have implications for structural complexity, nutrient cycling, water filtration, as well as carbon sequestration on the SEFRT.
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Andersson, Lars Fredrik. "Bilateral shipping and trade : Swedish-Finnish experiences in the post-war period". Doctoral thesis, Umeå : Ekonomisk historia, Umeå universitet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-514.
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Pezzoni, Filho José Carlos [UNESP]. "Compactação de um cambissolo háplico com o tráfego de um trator skidder no arraste de pinus elliottii". Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/99745.
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pezzonifilho_jc_me_botfca.pdf: 1844947 bytes, checksum: 744ee36bfa2865a4d0115c65f128a2a7 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A compactação do solo tem sido considerada como um dos principais danos ocasionados pelas operações mecanizadas de colheita de madeira, sendo que ocorrem danos diretos ao solo, como a compactação do solo (aumento da densidade do solo), diminuição da aeração e da macroporosidade, presença de camada de impedimento ao crescimento radicular, disponibilidade de água, entre outros. Além dos danos diretos ocorrem os indiretos, que são restrição no crescimento das raízes das plantas, onde ocorrerá a diminuição do crescimento da parte aérea da planta, a susceptibilidade do solo ao processo erosivo, devido a camada compactada, entre outros. A extração de madeira com o trator Skidder é a etapa de colheita na qual se deve ter maior atenção, pois esta máquina provoca grandes danos ao solo, tanto pelo seu peso, quanto pelo arraste de árvores e fustes que realizam sulcos (recalques) no solo. Uma forma de diminuir a compactação do solo é deixar camada de resíduos florestais nos ramais de extração de madeira, com isso haverá a minimização do efeito de compressão do solo pelo trator Skidder com o peso da carga arrastada. O objetivo do presente trabalho foi avaliar o nível de compactação do solo até a 5ª vez que o trator Skidder trafegou no ramal secundário de extração de madeira de Pinus (Pinus elliotti var. elliotti). A avaliação da compactação do solo na testemunha (densificação natural) até a 5ª passada demonstrou que houve compactação até a última vez que o trator Skidder trafegou na área, permitindo constatar que o tráfego de máquinas e fuste nas áreas de colheita promove a compactação do solo. Na interação entre os recalques e o número de passadas houve diferença nos níveis de compactação, sendo que com 5 passadas sobre a mesma área, o recalque do pneu apresentou uma menor compactação (1,34 Mg.m-3) quando comparado com o do fuste...
Soil compaction has been considered one of the major damage caused to the operations of mechanized harvesting, and direct damage occurs to the ground as soil compaction (increased bulk density), reduced aeration and macroporosity, the presence Layer impediment to root growth, water availability, among others. Besides the direct damage occurring indirect damages, which are restricting the growth of plant roots, which occur in the reduction of shoot growth of the plant, susceptibility to soil erosion due to the fact that the presence of the compacted layer, between other damage. To minimize such damage recommend carefully planning machinery traffic on the steps of forest harvesting. With this, the logging with tractor Skidder is the stage at which harvesting should be given more attention, because this machine causes significant damage to land, both by weight and the drag tree trunks and carrying grooves (track) in the soil. One way to reduce soil compaction is to leave layer of forest residues on the extensions of logging, thereby minimizing the effect will be to compress the soil by tractor Skidder with the weight of the load dragged.The aim of this study was to evaluate the level of soil compaction until the 5th time that the tractor Skidder the secondary extension of slash pine logging (Pinus elliottii var. Elliotii). The assessment of soil compaction in control (compression natural) until the 5th month showed that there was compaction until the last time that the tractor Skidder traffic in the area, allowing evidence that the traffic machines and tree trunks collection areas promote soil compaction. In the interaction between the track and the number of passes was no difference in levels of compression, with 5 being passed on to the same site, the track of the tire had a lower density (1.34 Mg.m-3) compared to the tree trunks (1.38 Mg.m-3). At both depths studied... (Complete abstract click electronic access below)
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Kayes, Edwin. "A NEW GENERATION OF DATA RECORDERS FOR REMOTE SENSING GROUND STATIONS". International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/608543.
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International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, NevadaMagnetic tape is the primary medium used to capture and store unprocessed data from remote sensing satellites. Recent advances in digital cassette recording technology have resulted in the introduction of a range of data recorders which are equally at home working alongside conventional recorders or as part of more advanced data capture strategies. This paper shows how users are taking advantage of the convenience, economy and efficiency of this new generation of cassette-based equipment in a range of practical applications.
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Pezzoni, Filho José Carlos 1984. "Compactação de um cambissolo háplico com o tráfego de um trator skidder no arraste de pinus elliottii /". Botucatu : [s.n.], 2011. http://hdl.handle.net/11449/99745.
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Resumo: A compactação do solo tem sido considerada como um dos principais danos ocasionados pelas operações mecanizadas de colheita de madeira, sendo que ocorrem danos diretos ao solo, como a compactação do solo (aumento da densidade do solo), diminuição da aeração e da macroporosidade, presença de camada de impedimento ao crescimento radicular, disponibilidade de água, entre outros. Além dos danos diretos ocorrem os indiretos, que são restrição no crescimento das raízes das plantas, onde ocorrerá a diminuição do crescimento da parte aérea da planta, a susceptibilidade do solo ao processo erosivo, devido a camada compactada, entre outros. A extração de madeira com o trator Skidder é a etapa de colheita na qual se deve ter maior atenção, pois esta máquina provoca grandes danos ao solo, tanto pelo seu peso, quanto pelo arraste de árvores e fustes que realizam sulcos (recalques) no solo. Uma forma de diminuir a compactação do solo é deixar camada de resíduos florestais nos ramais de extração de madeira, com isso haverá a minimização do efeito de compressão do solo pelo trator Skidder com o peso da carga arrastada. O objetivo do presente trabalho foi avaliar o nível de compactação do solo até a 5ª vez que o trator Skidder trafegou no ramal secundário de extração de madeira de Pinus (Pinus elliotti var. elliotti). A avaliação da compactação do solo na testemunha (densificação natural) até a 5ª passada demonstrou que houve compactação até a última vez que o trator Skidder trafegou na área, permitindo constatar que o tráfego de máquinas e fuste nas áreas de colheita promove a compactação do solo. Na interação entre os recalques e o número de passadas houve diferença nos níveis de compactação, sendo que com 5 passadas sobre a mesma área, o recalque do pneu apresentou uma menor compactação (1,34 Mg.m-3) quando comparado com o do fuste... (Resumo completo, clicar acesso eletrônico abaixo)Abstract: Soil compaction has been considered one of the major damage caused to the operations of mechanized harvesting, and direct damage occurs to the ground as soil compaction (increased bulk density), reduced aeration and macroporosity, the presence Layer impediment to root growth, water availability, among others. Besides the direct damage occurring indirect damages, which are restricting the growth of plant roots, which occur in the reduction of shoot growth of the plant, susceptibility to soil erosion due to the fact that the presence of the compacted layer, between other damage. To minimize such damage recommend carefully planning machinery traffic on the steps of forest harvesting. With this, the logging with tractor Skidder is the stage at which harvesting should be given more attention, because this machine causes significant damage to land, both by weight and the drag tree trunks and carrying grooves (track) in the soil. One way to reduce soil compaction is to leave layer of forest residues on the extensions of logging, thereby minimizing the effect will be to compress the soil by tractor Skidder with the weight of the load dragged.The aim of this study was to evaluate the level of soil compaction until the 5th time that the tractor Skidder the secondary extension of slash pine logging (Pinus elliottii var. Elliotii). The assessment of soil compaction in control (compression natural) until the 5th month showed that there was compaction until the last time that the tractor Skidder traffic in the area, allowing evidence that the traffic machines and tree trunks collection areas promote soil compaction. In the interaction between the track and the number of passes was no difference in levels of compression, with 5 being passed on to the same site, the track of the tire had a lower density (1.34 Mg.m-3) compared to the tree trunks (1.38 Mg.m-3). At both depths studied... (Complete abstract click electronic access below)
Orientador: Paulo Torres Fenner
Coorientador: Kléber Pereira Lanças
Banca: Ricardo Ralisch
Banca: Maria Helena Moraes
Mestre
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Min, Stephen K. "Properties of food and buffer solutions during high pressure processing in-situ measurement of density, compressibility, electrical conductivity and reaction volume /". Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1211910971.
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Morris, Evan Daniel. "The role of the low-density lipoprotein receptor in transport and metabolism of LDL through the wall of normal rabbit aorta in vivo. Estimation of model parameters from optimally designed dual-tracer experiments". Case Western Reserve University School of Graduate Studies / OhioLINK, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=case1055528562.
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Méndez, Vivas Darling Giyett Josefina [Verfasser]. "Density and subtypes of mast cells in the morphologically intact lower respiratory tract of subadult and adult cattle and in lungs of calves with pneumonia after experimental infection with Mycoplasma bovis / Darling Giyett Josefina Méndez Vivas". Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2016. http://d-nb.info/110687451X/34.
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Bozec, Xavier. "Etude par traces de cycles d'hysteresis sous champ alternatif de la dynamique de vortex dans les supraconducteurs YBaCuO et BiSrCaCuO monocristallins et dans la céramique YSmBaCuO". Toulouse, INSA, 1992. http://www.theses.fr/1992ISAT0013.
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Les phenomenes lies a l'ancrage des lignes de flux (vortex), constituent des problemes de grande importance pour les applications futures des supraconducteurs a haute temperature critique; un fort piegeage etant associe a des densites de courant critique elevees. Le travail que nous presentons sur la dynamique de vortex est en etroite relation avec ces mecanismes de piegeage. Nous etudierons dans ce memoire, les differents modeles regissant la dynamique de vortex qui peuvent intervenir dans des monocristaux d'ybacuo et de bisrcacuo ainsi que dans une ceramique ysmbacuo. Le trace de cycles d'hysteresis sous champ alternatif en fonction de la frequence et l'amplitude du champ va constituer le support experimental de notre etude. L'analyse de ces cycles etablira que les modeles de relaxation d'aimantation thermiquement activee expliquent correctement les resultats obtenus sur les cristaux d'ybacuo, permettant de mesurer des energies d'ancrage. Par contre, du fait d'une anisotropie plus prononcee et d'une chute de la densite de courant critique a haute temperature, nous mettrons en evidence dans les composes bisrcacuo, une dynamique de vortex gouvernee principalement par des forces de viscosite
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Salva, Martin. "Městský dům - architektura kombinace funkcí". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-225866.
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The project deals with completion a REC block buildings in Brno – Zábrdovice, defined by local roads. For the design of mass was used a porosity principle, when the site was covered with maximum static mass cutted by dynymic communication-optimal connections through the object. Object has five floors and a basement with garages and technical facilities. In the 1st floor and the part of 2nd floor are business premises, on the 2nd and 3rd level are administrative premises. On the part of a 3rd floor and in 4NP and 5th floor there are apartments. The foundations of an object is the reinforced concrete slab, the constuction systém is formed by reinforced-concrete columns with brick walls. Ceilings and staircases are monolithic reinforced concrete. Object is topped by a flat roof, part of the roof is greened.
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França, Elvis Joacir de. "A biomonitoração da Mata Atlântica na conservação da biodiversidade: espécies arbóreas nativas acumuladoras de elementos químicos". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-17102006-170028/.
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O projeto BIOTA Diversidade, dinâmica e conservação de florestas do Estado de São Paulo: 40 ha de parcelas permanentes vem sendo conduzido para o conhecimento dos processos geradores, mantenedores e reguladores da biodiversidade nas principais formações vegetacionais do Estado. Uma parcela permanente de 10 ha foi instalada na unidade de conservação correspondente à Floresta Ombrófila Densa (Mata Atlântica) para a caracterização completa do ecossistema. A investigação de elementos químicos nesse ecossistema altamente ameaçado foi desenvolvida nesta Tese de Doutoramento. Diversos processos são responsáveis pela manutenção de ecossistemas naturais. À ciclagem mineral corresponde o caminhamento dos elementos químicos, que fluem entre os compartimentos bióticos (folha e serrapilheira) e abióticos (atmosfera e solo). A complexidade desse mecanismo regulatório está relacionada com a deficiência, a toxicidade, a fitodisponibilidade e as interações dos elementos químicos, além das condições ambientais de crescimento como luminosidade, temperatura e umidade. Devido à sua adaptabilidade, as plantas absorvem elementos químicos, acumulando-os nos seus tecidos. A acumulação é ativa, ou seja, independentemente do meio, as plantas mantêm as concentrações de determinados elementos. Essa característica corrobora o uso desses organismos para a quantificação da qualidade do ambiente a partir dos estudos de biomonitoração de poluição atmosférica. A análise por ativação neutrônica instrumental INAA foi a técnica analítica empregada para a biomonitoração devido ao seu nível metrológico elevado e sua capacidade de determinação simultânea de diversos elementos. Para a comparabilidade dos resultados gerados, a qualidade do procedimento analítico, a representatividade das amostras e o efeito da contaminação com particulados de terra aderida à superfície das folhas foram também estudados. Os compartimentos solo, serrapilheira e folha tiveram sua composição química avaliada por INAA. De modo geral, foram detectadas concentrações totais de elementos químicos mais elevadas nos solos de vales (baixa altitude) do que nas regiões de alta altitude (solos mais desenvolvidos). Essa variabilidade não foi determinante das concentrações encontradas nas folhas, indicando a composição química elementar intrínseca das plantas. As concentrações nas folhas também não se alteraram significativamente (nível de 95% de confiança) de acordo com os resultados provenientes de quatro épocas de coleta diferenciadas. Foram identificadas espécies acumuladoras dos nutrientes Ca, Co, K, Na, Se e Zn, dos elementos traços Br, Ba, Cs, Hg, Rb, Sc, Sr e dos lantanídeos Ce, La e Sm. A utilização das espécies arbóreas para a biomonitoração da parcela permanente proporcionou o conhecimento das concentrações naturais dos elementos químicos. O trecho de Mata Atlântica avaliado foi considerado de baixo nível de poluição, pois a maior parte das espécies estudadas apresentou concentrações dos elementos químicos dentro da faixa esperada, com exceção das espécies naturalmente acumuladoras. Elementos traços como As, Cd, Cr e Ni ficaram abaixo dos limites de detecção. O trabalho concentrou esforços para o estabelecimento de padrões de referência para estudos de impacto ambiental considerando a composição química da parcela permanente da Mata Atlântica. O reservatório de elementos químicos no ecossistema foi estimado, evidenciando-se a importância desse conhecimento para a conservação da biodiversidade.The BIOTA Project Diversity, dynamic and conservation of forests from the São Paulo State: 40 ha of permanent parcels has been conducted to provide the knowledge on the generation, sustainability and regulation processes of the biodiversity of the State. A long-term plot (permanent parcel) was installed in the conservation unit corresponding to the Dense Ombrophilous Forest (Atlantic Forest) for the environmental characterization of the ecosystem. The investigation of chemical elements in this highly threatened forest was performed in this Doctorate Thesis. Several processes are responsible for the sustainability of the natural ecosystems. Mineral cycling defines the pathway of chemical elements from non-biotic compartments (soil and atmosphere) to biotic compartments (leaf and litter). The complexity of this regulatory mechanism is related to the deficiency, toxicity, phytoavailability and the interactions of the chemical elements, in addition to environmental growth conditions like luminosity, temperature and humidity. Due to its adaptability, plants are able to uptake and accumulate chemical elements in their tissues. This accumulation is an active process in which the plants tend to maintain the concentrations of some chemical elements independently of the environmental conditions. Such characteristic corroborates the use of these organisms for quantifying the environmental quality by biomonitoring studies of atmospheric pollution. Instrumental neutron activation analysis INAA was the analytical technique employed for biomonitoring due to its high metrological level and its capability for simultaneous determination of several chemical elements. For the comparability of the results, the quality of analytical procedure, the representativeness of samples and the effect of contamination with earth particles adhered to the leaf surface were also studied. The chemical composition of the soil, litter and leaf compartments was evaluated by INAA. The concentrations of some elements were higher for the soils of the valleys and considerably lower for the soils at higher altitudes. Such variability was not observed for the concentrations found in leaves, indicating the intrinsic chemical composition in plants. The concentrations in leaf did not change significantly (at the 95% confidence level) as demonstrated by the results from four different periods of sampling. Some tree species were able to accumulate the nutrients Ca, Co, K, Na, Se and Zn, the trace elements Br, Ba, Cs, Rb, Sc and Sr and the lanthanides Ce, Eu, La, Sm, Tb and Yb. The use of plants species for biomonitoring the long-term plot provided knowledge on the background concentrations of chemical elements. The Atlantic Forest can be considered to have a low status of pollution since most plants have shown concentrations within the expected range with exception of the accumulator species. Concentrations of some trace elements like As, Cd, Cr and Ni were below the detection limits. This work concentrated efforts to establish reference standards for studies on environmental impact considering the chemical composition in the long-term plot of the Atlantic Forest. The reservoir of chemical elements in the ecosystem was estimated, evidencing the importance of such knowledge for the biodiversity conservation.
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Zhang, Yumo. "PILOT SCALE DEMONSTRATION AND EVALUATION OF INNOVATIVE NON-DESLIMED NON-CLASSIFIED GRAVITY-FED HM CYCLONE". UKnowledge, 2015. http://uknowledge.uky.edu/mng_etds/19.
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Coal preparation plants are required in some cases to produce a high-grade product using a low specific gravity cut-point. For these situations, a second higher gravity separation would be desirable to generate a mid-grade product that can be utilized for electricity generation thereby maximizing coal recovery. A study was conducted to evaluate the potential of achieving efficient separations at two different density cut-points in a single stage using a three-product dense medium cyclone. Variations in density cut-point and process efficiency values were quantified as a function of the feed medium density, feed medium-to-coal ratio, and feed pressure using a three-level experimental design program. Results indicate the ability to effectively treat coal over a particle size range from 6mm to 0.15mm while achieving both low- and high-density cut-points up to 1.95 relative density. Ash content decreased from 27.98% in the feed to an average of 7.77% in the clean coal product and 25.76% in the middlings product while sulfur content was reduced from 3.87 to 2.83% in the clean coal product. The overall combustible recovery was maintained above 90% while producing clean coal products with ash and total sulfur content as low as 5.85 and 2.68%, respectively. Organic efficiency values were consistently about 95% and probable error values were in the range of 0.03 to 0.05, which indicates the ability to provide a separation performance equivalent to or better than traditional coal cleaning technologies.
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Vacula, Richard. "Nové metody záznamu a reprodukce optické zvukové stopy 16mm filmu". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242157.
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The work deals with the recording and reproduction of sound tracks on 16mm film and with old forgotten film optic sound technologies, as well as plans experiments and research, which examines possible methods for reading and writing tracks using modern optoelectronic devices. The final output is intended to drive the writing negative audio (analog and digital) on the photosensitive material and design of the device for synchronous playback of digital audio tracks from an external memory card. The work is done in collaboration with film laboratories Barrandov Studio a.s. and Meopta-Optika, spol. s r.o.
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Roig, Tierno Honorat. "Análisis de áreas comerciales mediante técnicas SIG: Aplicación a la distribución comercial y centros tecnológicos". Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/32832.
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Esta Tesis centra la atención en la aplicación que los SIG pueden tener en diferentes campos de la economía como las empresas minoristas o los centros tecnológicos intensivos en conocimiento.
Los SIG pueden definirse como el conjunto de herramientas para recoger, almacenar, transformar y mostrar los datos espaciales para un conjunto particular de propósitos (Burrough, 1988). Por su parte, Barredo (1996) precisa que los SIG son sistemas digitales que, a través de un conjunto de herramientas de hardware y de software, permiten el análisis y manipulación de datos geográficos proporcionando una modelación de la realidad.
Por una parte, en el sector minorista, la apertura de un nuevo local es un factor crítico ya que comporta una serie de riesgos monetarios y de imagen muy elevados para la empresa. Por ello, resulta clave realizar un correcto análisis de la localización para las nuevas aperturas (Hernández & Bennison, 2000). El uso de los SIG ha facilitado la comprensión de la información geográfica para los gerentes que carecen de conocimientos técnicos, ayudándoles, por tanto, a tomar decisiones difíciles y de gran envergadura (Ozimec et al., 2010). Además, los SIG son capaces de gestionar la información cartográfica con datos alfanuméricos. Por ello, los SIG se están convirtiendo en una herramienta indispensable para la toma de decisiones sobre la localización de establecimientos (Mendes & Themido, 2004).
Por otra parte, los centros tecnológicos, cuando se conciben como proveedores de servicios avanzados para permitir la innovación (COTEC, 2003), también pueden ser considerados ¿minoristas¿ cuyo producto son los servicios intensivos en conocimiento o knowledge intensive business services (KIS). Por lo tanto, el concepto de trade areas también se puede aplicar a los centros tecnológicos en cuanto a su ubicación y el diseño de sus estrategias, entre otros aspectos. Así, diferentes autores destacan la importancia de la proximidad geográfica de los centros de tecnología para que puedan ofrecer un servicio eficaz y apoyar a las empresas (Barrio & García-Quevedo, 2005; Tödtling & Kaufmann, 2001). Por ello, en la investigación que se llevará a cabo en esta Tesis, también se aplicarán técnicas GIS a los centros tecnológicos, en un intento de mejorar el conocimiento sobre los determinantes de la distribución espacial entre las empresas asociadas a un centro tecnológico.Roig Tierno, H. (2013). Análisis de áreas comerciales mediante técnicas SIG: Aplicación a la distribución comercial y centros tecnológicos [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/32832
TESIS
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Kerbal, Sofiane. "Development of new criteria for train detection and evaluation in critical conditions". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-253201.
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Railway signaling is of paramount importance to ensure traffic management andsafety on the rail network. The main lines are divided into sections called ‘blocks’,which are governed by a fixed signal installation. To prevent trains from colliding,each block allows one train at once. In France (and most European countries),train detection is performed by an electrical device called track circuit that consistsof a transmitter and a receiver installed at the track-side, and connected via therails. In the absence of a train, an electrical signal flows from the transmitter tothe receiver through the rails. As a train enters a track circuit, its axles shuntthe rails, provoking a short circuit (also called ‘shunt’): the signal transmitted tothe receiver drops. The detection of that signal drop results in the detection of atrain. This method rarely fails throughout the network, but there can be criticalcases where it may be inefficient. In this Master’s Thesis, new detection criteriaproposed in previous studies have been tested on signals measured in poor shuntingconditions. Three approaches have been tested: one in the time domain and two inthe frequency domain. The time approach compares the short-term and long-termstatistics of the received signals. The observation of a change in the spectra of thereceived signals around the 3rd order harmonic (3OH) has led to the implementationof two frequency criteria: the estimation of the band power around the 3OH andthe detection of the 3OH peaks. The obtained results show that better detection isachieved when the new criteria and the existing one are combined.Tågsignalsystem är väsentliga för att garantera trafikstyrning och säkerhet i tågnätet.Spåren är indelade i sektioner, s.k. block, som övervakas med fasta signalinstallationer.För att hindra tåg från att krocka, tillåts bara ett tåg i taget per block. IFrankrike (och de flesta andra europeiska länder), detekteras tågen med en elektriskspårkrets som består av en sändare och en mottagare som är installerad bredvidspåret och ansluten till rälsen. När inget tåg finns på spåret, flyter en elektrisk signalfrån sändaren till mottagaren via spåret. När ett tåg anländer, kortsluts kretsenav hjulaxeln och signalen försvinner från mottagaren. Minskningen i signalstyrkaanvänds för att detektera tåget. Denna metod sällan misslyckas i tågnätet, men iovanliga fall kan det uppstå farliga situationer. I detta examensarbete utvärderasnya detektionsmetoder, som har föreslagits i tidigare studier, på signaler som haruppmätts under förhållanden med dålig kontakt mellan hjul och spår. Tre olika metoderhar testats, en i tidsdomänen och två i frekvensdomänen. Tidsdomänsmetodenjämför kortvarig och långvarig statistik för den mottagna signalen. I spektrum förden mottagna signalen, har man observerat en förändring runt den tredje övertonen,samt detektering av frekvenstoppar vid tredje övertonen. De erhållna resultatenvisar på förbättrad detektering när de nya och existerande kriterierna kombineras.
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Hsiao, Pai-Yi. "Comportement critique des modèles de spin classiques sur des fractals : magnétisme orbital d'un gaz d'electrons bidimentionnel confiné par un potentiel harmonique". Paris 7, 2002. http://www.theses.fr/2002PA077099.
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(I) On étudie les comportements critiques du modèle d'Ising et dumodèle de Potts à 3 états sur des fractals par simulation Monte Carlo. Les résultats obtenus par l'analyse en tailles finies satisfont larelation d'hyperscaling avec la dimension de Hausdorff; ils différentdes développements en epsilon. L'universalité de la transition sur cesfractals est faible. De plus, on mesure les exposants dynamiques del'algorithme de Wolff et on met en évidence une nouvelle loi d'échelle que satisfait la distribution de taille des amas. (II) On étudie ungaz d'électrons 2D confiné par un potentiel harmonique et on introduitune formule de trace exacte en appliquant la théorie des résidus. Onpeut montrer que le magnétisme présente trois comportements différents:Diamagnétisme de Landau, Oscillation de Haas-van Alphen et Fluctuation mésoscopique. En appliquant la méthode des états cohérents, on peutdonner une formule pour le courant induit par le champ externe(I) We study the critical behavior of Ising model and 3-state Pottsmodel on fractals by Monte Carlo simulation. The results obtained byfinite size scaling satisfy the hyperscaling relation with the Hausdorffdimension, but differ from the prediction of epsilon-expansion. Theuniversality of these phase transions is shown to be weak. Moverover, we measure the dynamical exponents of the Wolff algorithm and establisha new scaling law for the size distribution of Wolff clusters. (II) Westudy a 2D electron gas confined by an harmonic potential and introducean exact trace formula in application of the residue theorem. We showthat the magnetism presents three different behaviors: Landau Diamagnetism,de Haas-van Alphen Oscillation and Mesoscopic Fluctuation. In applyingthe coherent state method, we give a formula for current density inducedby the external magnetic field
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Ingberg, Claes-Mårten. "Type 1 diabetes mellitus: Aspects of long-term complications and body composition". Doctoral thesis, Uppsala University, Department of Medical Sciences, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3287.
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Studies concerning social consequences, gastrointestinal and urinary tract symptoms were conducted in a population-based cohort comprising patients with long-standing type 1 diabetes and matched control persons. Three different questionnaires were sent by mail to diabetic patients and control persons. After a mean duration of 28.7±2.6 years, compared to the controls the diabetic patients showed an almost 10 times higher mortality, a lower employment rate and greater need for welfare benefits. These differences were mainly due to diabetic late complications. Education, housing conditions, life-style, civil state, alcohol and smoking habits were similar in the two groups. The prevalence of gastrointestinal symptoms was significantly higher in the diabetic patients than in the controls, and this was found to be attributable to the female diabetic patients. Female diabetic patients had been treated with antibiotics for urinary tract infections more often than controls, they experienced more social problems than controls in daily life because of urinary tract problems and used clamps to prevent wetting more often than did controls.
Body composition and bone mineral density were evaluated in parts of the cohort with long-standing type 1 diabetes and control persons in another population-based cohort comprising diabetic females aged 16-19 years with type 1 diabetes since childhood and matched controls. Besides a tendency to reduced abdominal fat mass in diabetic males, no difference was observed in fat mass, muscle mass or bone mineral density between the patients with long-standing type 1 diabetes and controls. Significant correlations were found between insulin dosage and whole body fat mass in diabetic females and between serum cholesterol levels and abdominal fat mass in diabetic males. The female adolescents had a higher body mass index than the controls, and their overweight was shown to consist almost entirely of an increased fat mass. The distribution of fat, expressed as abdominal-to-leg ratio, correlated significantly to HbA1c and daily dosage of insulin. Bone mineral density did not differ between the groups. IGF I was significantly lower both in patients with long-standing type 1 diabetes and in the adolescent diabetic females compared with their matched controls.
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Quarz, Volker. "Die Generierung von Fahrwegstörungen für vorgegebene Spektraldichten mit Hilfe orthogonaler Funktionen". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1099488073625-41555.
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Fahrbahnunebenheiten und Gleislagestörungen können als Repräsentanten schwach stationärer Prozesse aufgefasst werden. Die Beschreibung der Qualitätsklassen von Fahrwegen erfolgt konventionell über die Spektraldichte (Leistungsdichte). Ausgehend von der Spektraldichte-Beschreibung wird die Generierung synthetischer Fahrwegstörungen für die numerische Simulation von Fahrzeugen als Mehrkörpersystem mit den Mitteln der Fourieranalyse und mit Hilfe von Wavelets untersuchtRoad unevenness and track irregularities can be considered as realisations of weakly stationary stochastic processes. A description of track quality levels is given by the (power)spectral density of the related process. Here, the synthesis of track irregularities for a given spectral density using fourier series and wavelets is considered
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Pöschke, Patrick. "Influence of Molecular Diffusion on the Transport of Passive Tracers in 2D Laminar Flows". Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19526.
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In dieser Arbeit betrachten wir das Strömungs-Diffusions-(Reaktions)-Problem für
passive Markerteilchen, die in zweidimensionalen laminaren Strömungsmustern mit
geringem thermischem Rauschen gelöst sind. Der deterministische Fluss umfasst Zellen
in Form von Quadraten oder Katzenaugen. In ihnen tritt Rotationsbewegung auf.
Einige der Strömungen bestehen aus wellenförmigen Bereichen mit gerader Vorwärtsbewegung.
Alle Systeme sind entweder periodisch oder durch Wände begrenzt. Eine
untersuchte Familie von Strömungen interpoliert kontinuierlich zwischen Reihen von
Wirbeln und Scherflüssen. Wir analysieren zahlreiche numerische Simulationen, die
bisherige theoretische Vorhersagen bestätigen und neue Phänomene offenbaren. Ohne
Rauschen sind die Teilchen in einzelnen Bestandteilen des Flusses für immer gefangen.
Durch Hinzufügen von schwachem thermischen Rauschen wird die normale Diffusion
für lange Zeiten stark verstärkt und führt zu verschiedenen Diffusionsarten für
mittlere Zeiten. Mit Continuous-Time-Random-Walk-Modellen leiten wir analytische
Ausdrücke in Übereinstimmung mit den numerischen Ergebnissen her, die je nach
Parametern, Anfangsbedingungen und Alterungszeiten von subdiffusiver bis superballistischer
anomaler Diffusion für mittlere Zeiten reichen. Wir sehen deutlich, dass
einige der früheren Vorhersagen nur für Teilchen gelten, die an der Separatrix des
Flusses starten - der einzige Fall, der in der Vergangenheit ausführlich betrachtet wurde
- und dass das System zu vollkommen anderem Verhalten in anderen Situationen
führen kann, einschließlich einem Schwingenden beim Start im Zentrum einesWirbels
nach einer gewissen Alterungszeit. Darüber hinaus enthüllen die Simulationen, dass
Teilchenreaktionen dort häufiger auftreten, wo sich die Geschwindigkeit der Strömung
stark ändert, was dazu führt, dass langsame Teilchen von schnelleren getroffen werden,
die ihnen folgen.
Die umfangreichen numerischen Simulationen, die für diese Arbeit durchgeführt
wurden, mussten jetzt durchgeführt werden, da wir die Rechenleistung dafür besitzen.In this thesis, we consider the advection-diffusion-(reaction) problem for passive tracer particles suspended in two-dimensional laminar flow patterns with small thermal noise. The deterministic flow comprises cells in the shape of either squares or cat’s eyes. Rotational motion occurs inside them. Some of the flows consist of sinusoidal regions of straight forward motion. All systems are either periodic or are bounded by walls. One examined family of flows continuously interpolates between arrays of eddies and shear flows. We analyse extensive numerical simulations, which confirm previous theoretical predictions as well as reveal new phenomena. Without noise, particles are trapped forever in single building blocks of the flow. Adding small thermal noise, leads to largely enhanced normal diffusion for long times and several kinds of diffusion for intermediate times. Using continuous time random walk models, we derive analytical expressions in accordance with numerical results, ranging from subdiffusive to superballistic anomalous diffusion for intermediate times depending on parameters, initial conditions and aging time. We clearly see, that some of the previous predictions are only true for particles starting at the separatrix of the flow - the only case considered in depth in the past - and that the system might show a vastly different behavior in other situations, including an oscillatory one, when starting in the center of an eddy after a certain aging time. Furthermore, simulations reveal that particle reactions occur more frequently at positions where the velocity of the flow changes the most, resulting in slow particles being hit by faster ones following them. The extensive numerical simulations performed for this thesis had to be done now that we have the computational means to do so. Machines are powerful tools in order to gain a deeper and more detailed insight into the dynamics of many complicated dynamical and stochastic systems.
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Reuther, Theresa Maria. "Vergleich der Stabilität von Schanzschrauben im Knochen im externen Fixateurverbund zu ausgewählten Zeitpunkten am Schafmodell". Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2006. http://dx.doi.org/10.18452/15482.
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Externe Fixateure werden häufig für die Stabilisierung und Behandlung schwerer Frakturen genutzt. Schraubenkanalinfektionen können dabei zu Komplikationen, wie Osteomyelitis und Stabilitätsverlusten führen. Es ist unklar, ob Schraubenkanalinfektionen zu Schraubenlockerungen führen, oder aber ob der Stabilitätsverlust von Schrauben in Schraubenkanalinfektionen resultiert. Das Ziel dieser Studie ist es, einen Zusammenhang zwischen der mechanischen Stabilität, dem Auftreten von Infektionen und der osseären Verankerung darzustellen. An 27 Schafen wurde eine standardisierte Osteotomie (3mm weiter Frakturspalt) der rechten Tibia durchgeführt und mit einem monolateralem Fixateur externe stabilisiert. Während der täglichen Pinpflege wurde die Haut um die Schraubeneintrittsstellen begutachtet. Radiologische Verlaufskontrollen erfolgten in wöchentlichen Abständen. Nach 3, 6 und 9 Wochen wurden die Tiere getötet, die Ausdrehmomente der Schrauben gemessen und mikrobiologische Abstriche genommen. Knochenschnitte durch die Schraubenkanäle wurden für histologische, histochemische und histomorphometrische Analysen genommen. In dieser Studie scheint es zu einer Zunahme der Stabilisierung der osseären Verankerung während des Heilungsverlaufes zu kommen. Da die kortikale Knochendichte über die Zeit abnimmt, kann die zunehmend stabilere Verankerung der Schrauben einzig über eine gleichzeitige periostale Kallusdichtezunahme erklärt werden. Die größten Ausdrehmomente des neugebildeten periostalen Kallus wurden zum Sechswochenzeitpunkt gemessen. Danach nimmt die periostale Kallusfläche ab, wohingegen die Kallusdichte zunimmt. Die mikrobiologische Besiedelungsrate (15%) war dreifach höher als die klinisch bestätigten Infektionen. Hingegen war die Osteolyserate (28%) doppelt so hoch wie die mikrobiologisch bestätigte Infektionsrate. Eine Korrelation zwischen Infektion, Osteolyse und Pinlockerung konnte nicht gefunden werden.External fixators are frequently used for the stabilization and the treatment of problematic fractures. Pin track infections have been shown to cause complications such as osteomyelitis and loss of stability of osteosynthesis. It remains unclear, whether pin track infection provokes pin loosening, or loss of the pin stability results in pin track infections. The aim of this study was to investigate the correlation between the mechanical stability of pins, the incidence of pin track infections and the osseus anchorage of pins. 27 sheep underwent a standardized osteotomy (3 mm gap) of the right tibia. The tibiae were stabilized by a monolateral external fixator. Within the daily pin care routine, the skin around the pin entries was scored. Radiographs were taken at weekly intervals. After 3, 6 and 9 weeks, the animals were sacrificed, the extraction torque of all pins was determined and microbiological analyses were taken. Bone sections through the pintracks were taken for histological, histochemical and histomorphometrical analysis. This study reveals an increasing stability of osseous pinanchorage over the course of healing. As the cortical bone density decreased over time, the increased anchorage-stability of the pins can only be explained by the simultaneous increase of the periosteal callus bone density. The magnitude of the extraction force is determined by the newbuilt periosteal callus, which is at its biggest value at six weeks. Afterwards, the periosteal callus area abates, while the callus bone density accumulates. The microbiologically affirmed infection rate (15%) was three times higher than the one clinical ascertained. In contrast the evidence of osteolysis (28%) was twice as high as the microbiologically diagnosed infection-rate. Despite the low infection rate, evidence of cortical lysis coud not be prevented. No correlation could be found between infection, osteolysis and pin loosening.
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Vestin, Albin y Gustav Strandberg. "Evaluation of Target Tracking Using Multiple Sensors and Non-Causal Algorithms". Thesis, Linköpings universitet, Reglerteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-160020.
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Today, the main research field for the automotive industry is to find solutions for active safety. In order to perceive the surrounding environment, tracking nearby traffic objects plays an important role. Validation of the tracking performance is often done in staged traffic scenarios, where additional sensors, mounted on the vehicles, are used to obtain their true positions and velocities. The difficulty of evaluating the tracking performance complicates its development. An alternative approach studied in this thesis, is to record sequences and use non-causal algorithms, such as smoothing, instead of filtering to estimate the true target states. With this method, validation data for online, causal, target tracking algorithms can be obtained for all traffic scenarios without the need of extra sensors. We investigate how non-causal algorithms affects the target tracking performance using multiple sensors and dynamic models of different complexity. This is done to evaluate real-time methods against estimates obtained from non-causal filtering. Two different measurement units, a monocular camera and a LIDAR sensor, and two dynamic models are evaluated and compared using both causal and non-causal methods. The system is tested in two single object scenarios where ground truth is available and in three multi object scenarios without ground truth. Results from the two single object scenarios shows that tracking using only a monocular camera performs poorly since it is unable to measure the distance to objects. Here, a complementary LIDAR sensor improves the tracking performance significantly. The dynamic models are shown to have a small impact on the tracking performance, while the non-causal application gives a distinct improvement when tracking objects at large distances. Since the sequence can be reversed, the non-causal estimates are propagated from more certain states when the target is closer to the ego vehicle. For multiple object tracking, we find that correct associations between measurements and tracks are crucial for improving the tracking performance with non-causal algorithms.
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Berawi, Abdur. "Improving Railway Track Maintenance Using Power Spectral Density (PSD)". Tese, 2013. http://hdl.handle.net/10216/75018.
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Berawi, Abdur Rohim Boy. "Improving Railway Track Maintenance Using Power Spectral Density (PSD)". Doctoral thesis, 2013. https://repositorio-aberto.up.pt/handle/10216/70610.
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Berawi, Abdur Rohim Boy. "Improving Railway Track Maintenance Using Power Spectral Density (PSD)". Tese, 2013. https://repositorio-aberto.up.pt/handle/10216/70610.
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陳星光. "The design on the LQG/LTR servo controller of high track density optical disk drives". Thesis, 1990. http://ndltd.ncl.edu.tw/handle/88560356658026367779.
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