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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Riskbedömning av trikloretylenförekomster : MIFO-inventering fas 1 och en jämförelse mellan traditionella och alternativa karakteriseringsmetoder

Skröder, Theres January 2014 (has links)
Västerås is a city with an industrial heritage. One of the larger companies in Västerås is ABB AB, which has multiply businesses located at the area Finnslätten. High concentrations of trichloroethene (TCE) were found in the soil and groundwater at Finnslätten 1 during a phase II environmental site assessment. Due to the result of the assessment a supplementary investigation and a site specific risk assessment were made of building 358. The source zone and plume of trichloroethene have not been characterized even after several investigations at the site. The aim of this study was to make a risk assessment of three other buildings inside the area were degreasing with TCE have historical taken place. The collected information resulted in a risk class 2 of the three objects and shows that the buildings might be potential pre-emission sources of trichloroethene. The second aim contains a comparison between traditional and alternative approaches to enlighten the importance of effective characterization methods. Two potential characterization strategies were chosen; TRIAD approach and CMF approach. The result showed the importance of systematic project planning, dynamic work planning strategy and the use of multiple techniques to form the best “hybrid” during characterization of DNAPL. In order to bring the investigation to a successful conclusion it is of great importance to consider the uncertainties or diminish the uncertainties by collecting essential information.
2

The once and future Army : an organizational, political and social history of the Citizen Military Forces, 1947-1974

McCarthy, Dayton S., History, Australian Defence Force Academy, UNSW January 1997 (has links)
This thesis examines the Citizen Military Forces (CMF) from 1947 until it ceased to exist under that name with the release of the report of the Millar Inquiry in 1974. This thesis examines three broad areas: the organizational changes that the CMF adopted or had imposed upon it; the political decision-making surrounding the CMF; and a social analysis of the CMF which questions the viability and validity of a number of the CMF???s long held precepts. The thesis will show that the majority of circumstances and decisions surrounding the CMF were beyond its control. For example, the CMF could not change the prevailing military thought of the post-war period which emphasized increasingly the role of smaller, professional, readily-available armies. The first three chapters recount the CMF???s ???heyday??? in which the Army, assisted by National Service after 1950, was based around it and its influence at the highest levels was strongest. The next two chapters chronicle the background to Australia???s adoption of the ???Pentropic??? organization and the repercussions this had on the CMF. Chapters Six and Seven examine the consequences of the introduction of a second compulsory service scheme and the concomitant result which precluded the CMF from operational service in Vietnam. Chapters Eight and Nine deal with the Millar Inquiry, which offered the CMF a new hope, but in some regards, brought forth little beneficial gains for the CMF. The final chapters analyze some of the characteristics unique to the CMF, such as territorial affiliation, high turnover rates amongst the rank and file and the concept of the ???brilliant amateur???. This thesis concludes that, despite the mixed performance of the CMF, there is still a place for the citizen soldier in contemporary warfare, but far more consideration at the highest political and military levels must be given to the peculiar and difficult, but by no means insurmountable, problems citizen soldiering encounters in Australia.
3

The once and future Army : an organizational, political and social history of the Citizen Military Forces, 1947-1974

McCarthy, Dayton S., History, Australian Defence Force Academy, UNSW January 1997 (has links)
This thesis examines the Citizen Military Forces (CMF) from 1947 until it ceased to exist under that name with the release of the report of the Millar Inquiry in 1974. This thesis examines three broad areas: the organizational changes that the CMF adopted or had imposed upon it; the political decision-making surrounding the CMF; and a social analysis of the CMF which questions the viability and validity of a number of the CMF???s long held precepts. The thesis will show that the majority of circumstances and decisions surrounding the CMF were beyond its control. For example, the CMF could not change the prevailing military thought of the post-war period which emphasized increasingly the role of smaller, professional, readily-available armies. The first three chapters recount the CMF???s ???heyday??? in which the Army, assisted by National Service after 1950, was based around it and its influence at the highest levels was strongest. The next two chapters chronicle the background to Australia???s adoption of the ???Pentropic??? organization and the repercussions this had on the CMF. Chapters Six and Seven examine the consequences of the introduction of a second compulsory service scheme and the concomitant result which precluded the CMF from operational service in Vietnam. Chapters Eight and Nine deal with the Millar Inquiry, which offered the CMF a new hope, but in some regards, brought forth little beneficial gains for the CMF. The final chapters analyze some of the characteristics unique to the CMF, such as territorial affiliation, high turnover rates amongst the rank and file and the concept of the ???brilliant amateur???. This thesis concludes that, despite the mixed performance of the CMF, there is still a place for the citizen soldier in contemporary warfare, but far more consideration at the highest political and military levels must be given to the peculiar and difficult, but by no means insurmountable, problems citizen soldiering encounters in Australia.
4

Développement d'une modélisation du devenir de pesticides à l'échelle d'un versant au sein d'une plateforme hydrologique, prise en compte de la macroporosité / Computer modeling of pesticide fate at hillslope scale within a hydrological modeling framework taking into account macroporosity

Djabelkhir, Karima 21 July 2015 (has links)
L’objectif général de ma thèse est de développer une modélisation spatialisée à l’échelle d’un versant, afin de mieux rendre compte des principales voies de transfert des pesticides dans les terrains agricoles. Je cherche à adopter une approche simplifiée, mais qui permet néanmoins de représenter les discontinuités existantes (parcelles, fossés, talus … etc). En effet, on souhaite pouvoir quantifier les mécanismes du transfert des pesticides en prenant en compte l’influence des éléments du paysage (parcelles, fossés, bandes enherbées …etc) sur la partition des transferts d’eau et de pesticides en surface et en subsurface. On s’appuie pour ce développement sur les données acquises sur le bassin versant expérimental de la Morcille (69), qui servent à fournir des ordres de grandeur et un cadre pour tester la pertinence des développements effectués. Une synthèse bibliographique sur les processus en jeu et les modèles existants a conduit au choix de la plateforme de modélisation hydrologique CMF, développée à l’université de Giessen (Kraft, 2012). Cette dernière permet une modélisation orientée objet d’un système hydrologique (colonne de sol, versant, bassin versant ...etc) et propose une grande variété d’équations physiques pour la représentation des processus hydrologiques. Le travail est mené sur trois étapes, une première consiste à l’évaluation du comportement de la plateforme et la validation de sa réponse via la comparaison dans un premier temps via un modèle 1D suite à une comparaison avec Hydrus1D. Dans un second temps, nous avons mené des simulations en 2D en comparant avec le modèle Cathy en se basant sur les travaux de Sulis et al. (2010) et avec Hydrus2D (Simunek et al., 1999 & Simunek et al., 2001) sur un versant inspiré du versant expérimental de la Morcille. La deuxième étape consiste à la prise en compte des écoulements préférentiels dans certains types de sol structurés, nous paraît nécessaire pour une meilleure représentation des processus en jeu. La représentation du transfert préférentiel des produits phytosanitaires via les macropores vers la ressource en eau représente encore un défi pour la recherche. L’approche à double perméabilité (DP) choisie contient le développant d’une nouvelle fonction d’infiltration dans les macropores. Notre modèle DP contient également deux fonctions alternatives d’échange matrice-macropores ; la première est proportionnelle à la différence des teneurs en eau des deux compartiments du sol (Philip, 1968). La deuxième fonction d’échange est une onde diffusante basée sur l’approche présentée par van Genuchten (1993). La dernière partie de la thèse consiste en la modélisation des solutés suivant successivement les deux approches : simple porosité et double perméabilité, en considérant le transport des solutés par convection et une adsorption linéaire. La validation de notre approche de modélisation est menée en comparant avec les simulations d’Hydrus1D/2D. / The aim of my thesis is to develop a spatial scale modeling of a catchment, to better reflect the main pathways of pesticides in agricultural lands. We are looking to adopt a simplified approach, yet it allows to represent the existing discontinuities (plots, ditches, embankments ... etc). Indeed, we wish to quantify the mechanisms of transfer of pesticides taking into account the influence of landscape features (patches, ditches, grass strips ... etc) on the partition of water transfers and pesticides in surface and subsurface. It relies for this development on the acquired data on the experimental watershed Morcille (69), which serve to provide orders of magnitude and a framework to test the relevance of business developments. A literature review on the processes involved and the existing models led to the choice of hydrological modeling framework CMF, developed at the University of Giessen (Kraft, 2012). CMF allows for object oriented modeling of a hydrologic system (soil column, slope, watershed etc.) and offers a wide variety of physical equations for the representation of hydrological processes. The work is conducted in three steps, the first involves assessing the behavior of CMF and validating its response via the comparison initially via a 1D model following a comparison with Hydrus1D. Secondly, we conducted 2D simulations comparing with the Cathy model based on the work of Sulis et al. (2010) and Hydrus2D (Simunek et al., 1999 & Simunek et al., 2001) on a hillslope inspired from the experimental slope of Morcille. The second step is to take account of preferential flow in certain types of structured soil, seems necessary for better representation of the processes. The representation of the preferential transfer of pesticides through macropores to water resources is still a research challenge. The dual permeability approach (DP) contains selected developing the infiltration of a new function in the macropores. Our DP model also contains two alternative exchange functions matrix-macropores; the first one is proportional to the difference of the water contents of the two compartments of the soil (Philip, 1968). The second exchange function is a diffusing wave based on the approach outlined by van Genuchten (1993). The last part of the thesis consists in the modeling of solutes successively following two approaches: single dual porosity and permeability, considering the convective transport of solutes and a linear adsorption. The validation of our modeling approach is conducted by comparing with the Hydrus1D / 2D simulations.
5

Australia's citizen soldiers, 1919-1939 : a study of organisation, command, recruiting, training and equipment

Neumann, Claude, Dept. of History, Australian Defence Force Academy, UNSW January 1978 (has links)
The main problem investigated is how successful Australia???s citizen soldiers would have been in fulfilling either their anti-invasion or their anti-raid roles between 1919 and 1939. The organization, command, training, equipment, social composition, recruitment and retention of Australia???s citizen soldiers are examined in an effort to discover the solution to this problem. The conclusion reached is that Australia???s citizen soldiers could not have fulfilled their roles, the nature of which was widely debated by British and Australian defence planners because of their differing threat perceptions. Inter-Service rivalry over money also encouraged this debate. Basically, the A.M.F. did not have the equipment and trained troops to enable it to concentrate in time to repel a Japanese raid or invasion. Motor vehicles could have provided this mobility but their expense was prohibitive. However, in other respects the Military Board failed to make the best use of its resources. Slight changes in organization and the command structure might have made the C.M.F., once concentrated, more efficient and better able to fight the Japanese. More attention paid to ensuring that training was imaginative and interesting then might have led to higher retention rates, thereby eliminating the expensive and wasteful requirement for constant recruiting campaigns
6

Australia's citizen soldiers, 1919-1939 : a study of organisation, command, recruiting, training and equipment

Neumann, Claude, Dept. of History, Australian Defence Force Academy, UNSW January 1978 (has links)
The main problem investigated is how successful Australia???s citizen soldiers would have been in fulfilling either their anti-invasion or their anti-raid roles between 1919 and 1939. The organization, command, training, equipment, social composition, recruitment and retention of Australia???s citizen soldiers are examined in an effort to discover the solution to this problem. The conclusion reached is that Australia???s citizen soldiers could not have fulfilled their roles, the nature of which was widely debated by British and Australian defence planners because of their differing threat perceptions. Inter-Service rivalry over money also encouraged this debate. Basically, the A.M.F. did not have the equipment and trained troops to enable it to concentrate in time to repel a Japanese raid or invasion. Motor vehicles could have provided this mobility but their expense was prohibitive. However, in other respects the Military Board failed to make the best use of its resources. Slight changes in organization and the command structure might have made the C.M.F., once concentrated, more efficient and better able to fight the Japanese. More attention paid to ensuring that training was imaginative and interesting then might have led to higher retention rates, thereby eliminating the expensive and wasteful requirement for constant recruiting campaigns
7

Lignocellulose deconstruction using glyceline and a chelator-mediated Fenton system

Orejuela, Lourdes Magdalena 15 December 2017 (has links)
Non-edible plant biomass (lignocellulose) is a valuable precursor for liquid biofuels, through the processes of pretreatment and saccharification followed by fermentation into products such as ethanol or butanol. However, it is difficult to gain access to the fermentable sugars in lignocellulose, and this problem is principally associated with limited enzyme accessibility. Hence, biomass pretreatments that destroy native cell wall structure and allows enzyme access are required for effective biomass conversion techniques. This research studied two novel pretreatment methods on two wood species: 1) a deep eutectic solvent (DES) that, under heat, swells lignocellulose and partially solubilizes cell wall materials by causing breakage of lignin-carbohydrate linkages and depolymerization of the biomass components, and 2) a chelator-mediated Fenton reaction (CMF) that chemically modifies the nanostructure of the cell wall through a non-enzymatic cell wall deconstruction. After pretreatment, utilizing analytical techniques such as nuclear magnetic spectroscopy, wide angle x-ray scattering, and gel permeation chromatography, samples were analyzed for chemical and structural changes in the solubilized and residual materials. After single stage DES (choline-chloride-glycerol) and two stage, CMF followed by DES pretreatments, lignin/carbohydrate fractions were recovered, leaving a cellulose-rich fraction with reduced lignin and hemicellulose content as determined by compositional analysis. Lignin and heteropolysaccharide removal by DES was quantified and the aromatic-rich solubilized biopolymer fragments were analyzed as water insoluble high molecular weight fractions and water-ethanol soluble low molecular weight compounds. After pretreatment for the hardwood sample, enzyme digestibility reached a saccharification yield of 78% (a 13-fold increase) for the two stage (DES/CMF) pretreated biomass even with the presence of some lignin and xylan remained on the pretreated fiber; only a 9-fold increase was observed after the other sequence of CMF followed by DES treatment. Single stage CMF treatment or single stage DES pretreatment improved 5-fold glucose yield compared to the untreated sample for the hardwood sample. The enhancement of enzymatic saccharification for softwood was less than that of hardwoods with only 4-fold increase for the sequence CMF followed by DES treatment. The other sequence of treatments reached up to 2.5-fold improvement. A similar result was determined for the single stage CMF treatment while the single stage DES treatment reached only 1.4-fold increase compared to the untreated softwood. Hence, all these pretreatments presented different degrees of biopolymer removal from the cell wall and subsequent digestibility levels; synergistic effects were observed for hardwood particularly in the sequence DES followed by CMF treatment while softwoods remained relatively recalcitrant. Overall, these studies revealed insight into two novel methods to enhance lignocellulosic digestibility of biomass adding to the methodology to deconstruct cell walls for fermentable sugars. / Ph. D. / Wood is a valuable material that can be used to produce liquid biofuels. Wood main components are biopolymers cellulose, hemicellulose and lignin that form a complex structure. Nature has locked up cellulose in a protective assembly that needs to be destroyed to gain access to cellulose, convert it to glucose and then ferment it to bioalcohol. This process is principally associated with limited enzyme accessibility. Therefore, biomass pretreatments that deconstruct native cell wall structure and allow enzyme access are required for effective biomass conversion techniques. This research studied two novel pretreatment methods on two wood species: 1) a deep eutectic solvent called glyceline that, under heat, swells wood and partially solubilizes cell wall materials by causing breakage of bonds and converting it into smaller molecules (monomers and oligomers), and 2) a chelator-mediated Fenton system (CMF) that chemically modifies the structure of the cell wall. Pretreatments were tested individually and in sequence in sweetgum and southern yellow pine. After pretreatments, utilizing analytical techniques, fractions were investigated for chemical and structural changes in the solubilized and residual materials. Treated wood samples were exposed to enzymatic conversion. A maximum 78% of glucose yield was obtained for the glyceline followed by CMF pretreated wood. For yellow pine only a 24% of glucose yield was obtained for the CMF followed by glyceline treatment. All these pretreatments presented different degrees of biopolymer removal from the cell wall and subsequent enzyme conversion levels. Overall, these studies revealed insight into two novel methods to enhance wood conversion adding to the methodology to deconstruct cell walls for fermentable sugars.
8

Design Of A Three Phase AC-Side Common-Mode Inductor

Avyay Sah (15348511) 26 April 2023 (has links)
<p>In recent years, switch-mode power electronic converters have gained considerable popularity</p> <p>because of their compact size and high switching frequencies. This makes them</p> <p>suitable for power processing in various applications, including photovoltaic systems and</p> <p>electric vehicles. However, their high switching frequency capabilities have a drawback. A</p> <p>high-frequency common-mode voltage coupled with the switching of the power converters</p> <p>excites the parasitic capacitances of the system. It leads to the flow of common-mode current.</p> <p>Since the common-mode current flows through an unintended path, it can potentially</p> <p>interfere with the performance of system components. Passive filters can be used to mitigate</p> <p>common-mode currents. Using a common-mode inductor in conjunction with strategically</p> <p>placed capacitors makes it possible to limit the flow of common-mode current.</p> <p><br></p> <p>As part of this work, passive mitigation of common-mode current will be investigated in</p> <p>a variable frequency drive system. In this regard, the process of designing a three-phase ac</p> <p>common-mode inductor is explained. As a first step, a mitigation strategy is proposed and</p> <p>described. Next, the issue of self-capacitance of the inductor is discussed. Afterwards, the</p> <p>ac common-mode inductor is designed using a multi-objective optimization-based approach.</p> <p>Following this are the design results, concluding the dissertation.</p>
9

Závislost hodnot UV indexu na vybraných parametrech / Relationship between the UV index and selected parameters

Tomanová, Helena January 2021 (has links)
Relationship between the UV index and selected parameters Abstract Ultraviolet radiation (UV radiation) is a shortwave radiation with wavelengths from 100 to 400 nm. This radiation has both positive and negative effects on living organisms and human health. Therefor the so-called UV index (UVI), characterizing the biological effect of UV radiation on human health was defined in 1994. This thesis aims to evaluate the link between selected factors (total ozone column, solar elevation angel, cloudiness and altitude) and the UVI values. Observed data at four stations in Czechia (Hradec Králové, Košetice, Kuchařovice, Labská bouda) and SYNOP reports from the four nearest stations during the period 2010−2017 were used. The Sun elevation (angle of Sun ray) has the strongest effect on the UVI values. The highest UVI values are generally reached at high angels when the Sun rays go the shortest path through the atmosphere. The increase of the UVI is exponential, from an angle of 30ř the increase is approximately linear. The UVI values increase on average by 0.8 at the Hradec Králové station and by 0.9 at the Labská bouda station for angle increasing by 5ř. The effect of clouds is significant and depends on the height and the clouds amount. High level clouds reduce UVI negligible, overcast sky by only 15 %. Medium and...
10

The Role of Low-Molecular Weight Fungal Metabolites in Eutypa Dieback Grapevine Trunk Disease

Sebestyen, Dana 20 October 2021 (has links)
Eutypa dieback, one of several grapevine trunk diseases (GTDs), is of serious concern to the grape industry globally. This disease is caused by the fungus Eutypa lata but it is often seen in consortia growth with Phaeoacremonium minimum and Phaeomoniella chlamydospora. It is vital to understand the mechanisms for how this disease functions to develop control measures to combat it. Brown rot fungi are able to use a complex of low molecular weight (LMW) metabolites to induce a Fenton reaction to deconstruct woody tissue. These metabolites are part of a chelator mediated Fenton (CMF) chemistry that produces reactive oxygen species that are capable of depolymerizing wood polymers. We propose that a mechanism similar to CMF chemistry may be occurring in grapevine trunk disease pathogens. This thesis investigates how LMW metabolites produced by the fungi contribute to the disease and decay progression in GTDs. Research on Mite control in the laboratory with abamectin was also investigated, as research in this area was required when mites infested our fungal cultures and suitable laboratory controls were not available. Research on the GTD fungi was initiated by first examining whether metabolites produced by the three fungi can function in a manner to promote reactions like the CMF system. We separated and identified specific metabolites that potentially could contribute to CMF chemistry. We found that all three GTD fungi were able to produced LMW metabolites that promoted CMF chemistry, and we hypothesized that this mechanism contributes to processes leading to tissue necrosis in grapevine trunk wood. To explore the development of effective control measures based on this newly discovered mechanism for pathogenesis, we also explored the use of antioxidant/chelator compounds, BHA and BHT, in the control of the consortia fungi. Biocontrol organisms, Bacillus subtilis and Trichoderma atroviride, that produce antioxidants were also tested as biocontrols against the fungi involved in Eutypa Dieback disease. We found that BHA was highly effective in inhibiting fungal growth for all three fungi at concentrations higher than 0.5mM, and both B. subtilis and T. atroviride proved to be effective biocontrol agents in inhibiting E. lata, P. minimum, and P. chlamydospora.

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