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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.
91

Measurement, Characterization, and Source Apportionment of the Major Chemical Components of Fine Particulate Material, Including Semi-Volatile Species

Grover, Brett D. 16 February 2006 (has links) (PDF)
The promulgation of revised standards for atmospheric fine particles (PM2.5) by the US EPA has sparked renewed interest in the ability to accurately measure and characterize suspended atmospheric particulate matter. Semi-volatile material (SVM), consisting of ammonium nitrate and semi-volatile organic material (SVOM), is not accurately measured by EPA accepted methods such as the Federal reference method (FRM) or Tapered Element Oscillating Microbalance (TEOM). However, SVM is often a major fraction of urban aerosols. Recent advances in atmospheric sampling instrumentation allowed for the semi-continuous characterization of urban PM2.5, including SVM. The Filter Dynamic Measurement System (FDMS) was shown to measure total PM2.5 mass including semi-volatile species. Validation of the FDMS was performed by comparison with the particle concentrator-Brigham Young University organic sampling system (PC-BOSS) and the real-time total ambient mass sampler (RAMS). Semi-continuous ambient particulate concentrations of sulfate, nitrate and ammonium ion were measured by a newly developed Dionex instrument which was field tested and validated for the first time in Fresno, CA. Either a modified Sunset Laboratory carbon monitor, collocated with a conventional Sunset carbon monitor employing a common inlet, or the newly developed dual-oven Sunset monitor allowed for the semi-continuous determination of both nonvolatile and semi-volatile organic material. This was the first attempt to characterize both nonvolatile and semi-volatile fractions of an urban aerosol in a semi-continuous manner using all semi-continuous instruments. A suite of instruments for semi-continuous PM2.5 monitoring was recommended including, an R&P FDMS for the measurement of PM2.5 mass, a dual-oven Sunset monitor for the measurement of nonvolatile and semi-volatile carbonaceous species, and a Dionex GP-IC for the measurement of inorganic species. A TEOM monitor is also recommended to measure nonvolatile PM2.5 mass. Using these instruments, semi-continuous mass closure was obtained for the first time during a study conducted in Riverside, CA. The advantage of using semi-continuous sampler data in the application of source apportionment was elucidated. Local aerosols are often impacted by short-term pollution episodes that cannot be temporally resolved using integrated samplers. One-h averaged data applied to source apportionment models was shown to increase the power of the model to predict sources, both primary and secondary, that exhibit diurnal short-term episodes.
92

The contribution of justice MM Corbett to the development of the law of taxation in South Africa

Van der Walt, Wessel Johannes 30 September 2007 (has links)
Mr Justice Corbett made a substantial contribution to the South African tax law as he delivered several judgements during his long career on the bench. Starting from the lower ranks as a judge he became Chief Justice of South Africa. Precedents set by his judgements are considered important and indicative of the level of South African tax law. This dissertation observes his background, looks at the operations of the tax court in South Africa and examines whether his judgements were cited and applied in subsequent cases as accepted precedent. International case law is referred to, to compare his judgements with comparable international tax law. / Auditing / M. Comm. (Accounting)
93

Théorie économique de la réglementation des prix de transfert / The economics of transfer pricing regulation

Pellefigue, Julien 13 September 2012 (has links)
Le terme de « prix de transfert » désigne le prix des transactions conclues entre les filiales d’une même entreprise multinationale. La thèse traite, sous un angle essentiellement normatif, de la problématique de réglementation de ces prix, c'est-à-dire de la détermination du mode de partage optimal du profit d’un groupe entre ses filiales. La thèse s’attache tout d’abord à montrer l’effet de la réglementation des prix de transfert sur les décisions de production et d’investissement des entreprises, puis sur le bien-être mondial. Sur la base des résultats obtenus, les objectifs qu’un dictateur bienveillant international devrait assigner à ce type de réglementation sont ensuite établis. Ce double travail permet de tracer le contour d’un projet de réglementation optimale, fondé sur le concept d’équité inter-nations, et dont l’application conduirait à attribuer à chaque filiale sa valeur de Shapley dans un jeu préalablement défini. La thèse éclaire également le débat contemporain en proposant un protocole permettant de comparer le principe de pleine concurrence avec la méthode d’allocation forfaitaire. / The prices of the transactions set between subsidiaries of a multinational corporation are usually called « transfer prices ». The dissertation deals with the normative questions raised by the regulation of such prices, particularly the optimal way of distributing the profit of a multinational between its subsidiaries. The dissertation first shows how the transfer prices regulation can influence corporate production and investment decisions, thereby impacting worldwide welfare. Based upon these results, the objectives that an international benevolent dictator would pursue through such a regulation are then identified. This program allows for the sketching of an optimal transfer prices regulation, which relies strongly upon the inter-nation equity concept, and which application would grant each subsidiary its Shapley value in a certain game. The dissertation also makes a contribution to the current debate by proposing a protocol to compare the arm’s length principle with the formulary apportionment method.
94

Improving the discrimination of primary and secondary sources of organic aerosol : use of molecular markers and different approaches / Amélioration de la discrimination des sources primaires et secondaires de l'aérosol organique : utilisation de marqueurs moléculaires et de différentes approches

Srivastava, Deepchandra 26 April 2018 (has links)
Les aérosols organiques (AO), issus de nombreuses sources et de différents processus atmosphériques, ont un impact significatif sur la qualité de l’air et le changement climatique. L’objectif de ce travail de thèse était d’acquérir une meilleure connaissance de l’origine des AO par l’utilisation de marqueurs organiques moléculaires au sein de modèles source-récepteur de type positive matrix factorization (PMF). Ce travail expérimental était basé sur deux campagnes de prélèvements réalisées à Grenoble (site urbain) au cours de l’année 2013 et dans la région parisienne (site péri-urbain du SIRTA, 25 km au sud-ouest de Paris) lors d’un intense épisode de pollution aux particules (PM) en Mars 2015. Une caractérisation chimique étendue (de 139 à 216 espèces quantifiées) a été réalisée et l’utilisation de marqueurs moléculaires primaires et secondaires clés dans la PMF a permis de déconvoluer de 9 à 11 sources différentes de PM10 (Grenoble et SIRTA, de façon respective) incluant aussi bien des sources classiques (combustion de biomasse, trafic, poussières, sels de mer, nitrate et espèces inorganiques secondaires) que des sources non communément résolues telles que AO biogéniques primaires (spores fongiques et débris de plantes), AO secondaires (AOS) biogéniques (marin, oxydation de l’isoprène) et AOS anthropiques (oxydation des hydrocarbures aromatiques polycycliques (HAP) et/ou des composés phénoliques). En outre, le jeu de données obtenu pour la région parisienne à partir de prélèvements sur des pas de temps courts (4h) a permis d’obtenir une meilleure compréhension des profils diurnes et des processus chimiques impliquées. Ces résultats ont été comparés à ceux issus d’autres techniques de mesures (en temps réel, ACSM (aerosol chemical speciation monitor) et analyse AMS (aerosol mass spectrometer) en différée) et/ou d’autres méthodes de traitement de données (méthodes traceur EC (elemental carbon) et traceur AOS). Un bon accord a été obtenu entre toutes les méthodes en termes de séparation des fractions primaires et secondaires. Cependant, et quelle que soit l’approche utilisée, la moitié de la masse d’AOS n’était toujours pas complètement décrite. Ainsi, une nouvelle approche d’étude des sources de l’AO a été développée en combinant les mesures en temps réel (ACSM) et celles sur filtres (marqueurs moléculaires organiques) et en utilisant un script de synchronisation des données. L’analyse PMF combinée a été réalisée sur la matrice de données unifiée. 10 facteurs AO, incluant 4 profils chimiques différents en lien avec la combustion de biomasse, ont été mis en évidence. Par rapport aux approches conventionnelles, cette nouvelle méthodologie a permis d’obtenir une meilleure compréhension des processus atmosphériques liés aux différentes sources d’AO. / Organic aerosols (OAs), originating from a wide variety of sources and atmospheric processes, have strong impacts on air quality and climate change. The present PhD thesis aimed to get a better understanding of OA origins using specific organic molecular markers together with their input into source-receptor model such as positive matrix factorization (PMF). This experimental work was based on two field campaigns, conducted in Grenoble (urban site) over the 2013 year and in the Paris region (suburban site of SIRTA, 25 km southwest of Paris) during an intense PM pollution event in March 2015. Following an extended chemical characterization (from 139 to 216 species quantified), the use of key primary and secondary organic molecular markers within the standard filter-based PMF model allowed to deconvolve 9 and 11 PM10 sources (Grenoble and SIRTA, respectively). These included common ones (biomass burning, traffic, dust, sea salt, secondary inorganics and nitrate), as well as uncommon resolved sources such as primary biogenic OA (fungal spores and plant debris), biogenic secondary AO (SOA) (marine, isoprene oxidation) and anthropogenic SOA (polycyclic aromatic hydrocarbons (PAHs) and/or phenolic compounds oxidation). In addition, high time-resolution filter dataset (4h-timebase) available for the Paris region also illustrated a better understanding of the diurnal profiles and the involved chemical processes. These results could be compared to outputs from other measurement techniques (online ACSM (aerosol chemical speciation monitor), offline AMS (aerosol mass spectrometer) analyses), and/or to other data treatment methodologies (EC (elemental carbon) tracer method and SOA tracer method). A good agreement was obtained between all the methods in terms of separation between primary and secondary OA fractions. Nevertheless, and whatever the method used, still about half of the SOA mass was not fully described. Therefore, a novel OA source apportionment approach has finally been developed by combining online (ACSM) and offline (organic molecular markers) measurements and using a time synchronization script. This combined PMF analysis was performed on the unified matrix. It revealed 10 OA factors, including 4 different biomass burning-related chemical profiles. Compared to conventional approaches, this new methodology provided a more comprehensive description of the atmospheric processes related to the different OA sources.
95

Avaliação do uso de diferentes modelos receptores com dados de PM2,5: balanço químico de massa (BQM) e fatoração de matriz positiva (FMP)

Trindade, Camila Carnielli 13 March 2009 (has links)
Made available in DSpace on 2016-12-23T14:04:31Z (GMT). No. of bitstreams: 1 dissertacao Trindade.pdf: 2131237 bytes, checksum: 514907f9bd367cc5bd486dcd27fa2d9d (MD5) Previous issue date: 2009-03-13 / A identificação de fontes para material particulado tem sido um tema de crescente interesse em todo o mundo para auxiliar a gestão da qualidade do ar. Esta classe de estudos é convencionalmente baseada no uso de modelos receptores, que identificam e quantificam as fontes responsáveis a partir da concentração do contaminante no receptor. Existe uma variedade de modelos receptores disponíveis na literatura, este trabalho compara os resultados dos modelos receptores balanço químico de massa (BQM) e fatoração de matriz positiva (FMP) para o banco de dados de PM2,5, da região de Brighton, Colorado, com o intuito de investigar as dificuldades na utilização de cada modelo, bem como suas vantagens e desvantagens. Inicialmente, já é conhecido que o modelo BQM tem a desvantagem de necessitar dos perfis das fontes, determinados experimentalmente, para ser aplicado e também tem limitações quando as fontes envolvidas são similares. Já o modelo FMP não requer os perfis de fontes, mas tem a desvantagem de precisar de elevada quantidade amostral da concentração do contaminante no receptor. Os resultados mostraram, baseados nas medidas de performance que os dois modelos foram aptos para reproduzir os dados do receptor com ajustes aceitáveis. Todavia, resultados diferentes se ajustaram a medidas de performance. O modelo BQM, utilizou 9 tipos de fontes e o modelo FMP encontrou apenas 6 tipos de fontes. Constatou-se com isso que o modelo FMP tem dificuldades em modelar fontes que aparecem ocasionalmente. As fontes sulfato de amônio, solos, veículos a diesel e nitrato de amônio tiverem boas correlações nos resultados dos dois modelos de contribuições de fontes. Os perfis de fontes utilizados no modelo BQM e resultados do modelo FMP que mais se assimilaram foram das fontes nitrato de amônio, solos, sulfato de amônio e combustão de madeira e ou/ veículos desregulados. Verificou-se no modelo FMP que as espécies não características de determinadas fontes aparecem nos resultados dos perfis das fontes, o que torna-se ainda mais complexo a identificação das fontes, requerendo elevado conhecimento sobre a composição de inúmeras fontes. / The identification of sources of particulate matter has been a topic of growing interest throughout the world to assist the air quality management. This class of studies is conventionally based on the use of receptor models, which identify and quantify the sources responsible from the concentration of the contaminant in the receptor. There are a variety of receptor models, this study compares the results of chemical mass balance (CMB) and positive matrix factorization (PMF) models for a database of PM2.5, for the region of Brighton, Colorado, with a view to investigate the difficulties in the use of each model, as well as its advantages and disadvantages. It is known that the CMB model has the disadvantage of requiring source profiles, determined experimentally, to be applied and also has limitations when the sources involved are similar. On the other hand, the PMF model does not require source profiles, it has the disadvantage to require a large amount sample, in receptor. The results showed, based on performance measures that both models were able to reproduce the data of the receptor with reasonable fit. However, different results were adjusted for performance measurements. The CMB model, used 9 types of sources and PMF model found only 6 types of sources, it was noted by that what the PMF model has difficulty in modeling sources that appear occasionally. The sources ammonium sulfate, soil, diesel vehicles and ammonium nitrate have good correlation in the results of the two model of sources apportionment. The source profiles used in the CMB model and results of the PMF model that present more similarities were of the sources ammonium nitrate, soil, ammonium sulfate and combustion of wood and/or smoker vehicles. It was verified what the PMF model does not separate well species in the source profiles, therefore becomes even more complex to identify the sources in the FMP model, requiring considerable knowledge about the composition of many sources. For the database used with similar sources, the lack of confidence in the results based only on receptors models for a final decision on the source apportionment.
96

Characterization and source apportionment of ambient PM2.5 in Atlanta, Georgia: on-road emission, biomass burning and SOA impact

Yan, Bo 20 August 2009 (has links)
Characterization and Source Apportionment of Ambient PM2.5 in Atlanta, Georgia: On-Road Emission, Biomass Burning and SOA Impact Bo Yan 260 Pages Directed by Drs. Armistead G. Russell and Mei Zheng Various airborne PM2.5 samples were collected in the metropolitan Atlanta and surrounding areas, which are directly impacted or dominated by on-road mobile and other typical urban emissions, regional transport sources, prescribed burning plumes, wildfire plumes, as well as secondary sources with anthropogenic and biogenic nature in origin. Detailed PM2.5 chemical speciation was conducted including over one hundred of GC/MS-quantified organic compounds, organic carbon (OC), water-soluble organic carbon (WSOC), elemental carbon (EC), ionic species, and tens of trace metals. Day-night, seasonal and spatial variations of PM2.5 characterization were also studied. Contributions of PM2.5 major sources were identified quantitatively through the receptor source apportionment models. These modeling results, especially on-road mobile source contributions and secondary organic carbon (SOC) were assessed by multiple approaches. Furthermore, new season- and location-specific source profiles were developed in this research to reflect real-world and representative local emission characterizations of on-road mobile sources, aged prescribed burning plumes, and wildfire plumes. Secondary organic aerosol (SOA), a major component of PM2.5 in the summer, was also explored for sources and contributions.
97

Beyond partisanship? : federal courts, state commissions, and redistricting / Federal courts, state commissions, and redistricting

McKenzie, Mark Jonathan 28 August 2008 (has links)
My dissertation examines the influence of partisanship in decision making on redistricting in state commissions and judicial rulings. My central questions are twofold. First, do Republican- and Democratic-appointed federal judges engage in decision making that favors their respective parties? Second, what is the extent of partisan voting on bipartisan state redistricting commissions? These issues possess considerable substantive importance. Some states have considered moving redistricting responsibility out of the legislature and into state commissions, while some political scientists and legal scholars have suggested more vigorous court involvement in the regulation of redistricting. Implicit in many of these arguments is the assumption that federal courts and state commissions will act as neutral arbiters. But, very little social science research exists on the behavior of these institutions. My investigation combines quantitative and qualitative evidence, using interviews I conducted of federal judges and redistricting commissioners across the country, together with statistical analyses of court decisions and commission votes. I have 138 court cases from 1981 to 2006, totaling 414 observations or judicial votes. I argue that federal judges are neither neutral arbiters nor partisan maximizers. Rather, federal judges act as constrained partisans. Judges do not necessarily favor their own party's plans in court cases anymore than they do plans created by both parties under divided government. But, when a federal judge reviews a redistricting plan drawn up by a different party, and where the judge's own party is the victim of partisan line-drawing, she will be more attuned to issues of unfairness in the process. Under circumstances where Supreme Court precedent is unclear, partisan cues become more salient for the judge, increasing the probability she will rely on partisan influences to declare the plan invalid. Interestingly enough, these partisan effects in judicial voting vanish in cases where the Supreme Court delineates unambiguous rules, such as litigation concerning 1 person 1 vote equal population claims. My analysis of state redistricting commissions, based on the votes of commissioners and in-depth interviews with them, illustrates that commissions, like courts, are also not immune to partisan decision-making. Partisan factors tend to be the overriding concern of commissioners. / text
98

Legal Aspects of Urban Runoff Development

Chudnoff, D. A. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / The relationships between the separate disciplines of hydrology and law are analysed in this study into how water law and its strictures may impose upon the development of urban runoff in the metropolitan Tucson area. Brief descriptions of the doctrine of appropriation, diffuse surface waters and developed waters are presented to illustrate the complexities of the problem of urban runoff development. It is suggested that planners must not only be aware of the legal issues involved but also must understand the philosophy and principles of water law.
99

The contribution of justice MM Corbett to the development of the law of taxation in South Africa

Van der Walt, Wessel Johannes 30 September 2007 (has links)
Mr Justice Corbett made a substantial contribution to the South African tax law as he delivered several judgements during his long career on the bench. Starting from the lower ranks as a judge he became Chief Justice of South Africa. Precedents set by his judgements are considered important and indicative of the level of South African tax law. This dissertation observes his background, looks at the operations of the tax court in South Africa and examines whether his judgements were cited and applied in subsequent cases as accepted precedent. International case law is referred to, to compare his judgements with comparable international tax law. / Auditing / M. Comm. (Accounting)
100

CCCTB - The Employment Factor Game

Eberhartinger, Eva, Petutschnig, Matthias January 2014 (has links) (PDF)
The draft for a Common Consolidated Corporate Tax Base Directive in the European Union includes the suggestion for an apportionment formula which allocates taxable group profits to group member corporations. These allocated profits shall then be taxed in the respective Member States. The draft directive delegates the right to define one factor of the apportionment formula, the term "Employee" to the Member States, who are therefore free to choose a narrow or a broad definition, the latter including also atypical employment schemes. Using a game-theoretic approach the paper shows that the individually rational strategy of any Member State to define "Employee" broadly so as to maximize the volume of the apportionment factor and thus maximize the allocated share of taxable income is only the best solution when tax rate differences and differences in the volume of atypical employment schemes are disregarded. If such differentials and the corporate groups' reactions to different Member States' definitions are included in modelling the game's pay-offs a narrow definition of "Employee" yields the highest individual pay-offs to the Member States involved. This change of dominant strategies is triggered by the corporate group's shifting of the employment factor from high-tax to low-tax Member States. Our paper differs from previous research on the economic effects of the CCCTB apportionment formula as it is the first paper identifying and analysing the employment factor and its distorting effects. The paper discusses possible tax minimizing strategies for corporate groups by shifting workforce and develops a model to quantify these potential relocations. Furthermore the paper presents advice to policy makers in their "Employee" definition decision and shows how Member States could use this definition to both minimize outward factor shifting and maximize inward factor shifting.(authors' abstract) / Series: WU International Taxation Research Paper Series

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