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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

CSR och earnings management - agerar företagsledningen etiskt eller opportunistiskt? : En kvantitativ studie på kontinentaleuropeiska bolag

Hansson, Marcus, Svensson, Desirée January 2019 (has links)
Syfte: CSR är ett högaktuellt och viktigt ämne för företagen och deras intressenter. Då högre CSR- aktiviteter anses vara relaterat till etiskt agerande företagsledningar undersöker studien om företagens ledningar utnyttjar detta i försök att dölja omoraliska aktiviteter i form av earnings management. En opportunistiskt agerande företagsledning använder earnings management för att manipulera resultatet i önskad riktning, vilket kan göras genom diskretionära periodiseringar (AEM) eller via aktiviteter som påverkar kassaflödet (REM). Eftersom dessa fungerar som substitut så undersöks båda i studien. Studien baseras på kontinentaleuropeiska bolag där rättstillämpningen bygger på civil law. Dessa företag redovisar enligt IFRS och CSR-rapporterar efter GRI, vilket tidigare forskning pekat ut som faktorer som påverkar sambandet mellan CSR och earnings management. Syftet med studien är därför att undersöka om CSR används som ett medel för att dölja förekomsten av earnings management, samt om det finns stöd för ett opportunistiskt alternativt etiskt perspektiv. Metod: Studien har en kvantitativ forskningsmetod och tillämpar en positivistisk forskningsfilosofi med en hypotetisk-deduktiv ansats. Studien använder en tvärsnittsdesign med sekundärdata från kontinentaleuropeiska bolag över en tioårsperiod (2008-2017). Datan har hämtats från Thomson Reuters Datastream och analyserats i IBM SPSS. Resultat & slutsats: Resultaten indikerar att kontinentaleuropeiska företag agerar opportunistiskt och möjligtvis använder CSR i försök att dölja earnings management. Detta kan dock endast härledas till REM-aktiviteterna abnorma kassaflöden och abnorma produktionskostnader. Mellan CSR och AEM kunde inget samband redogöras. Därav dras slutsatsen att det är viktigt att earnings management studeras utifrån båda aspekterna för att erhålla ett rättvisande resultat. Examensarbetets bidrag: Studien bidrar till att fylla forskningsgapet gällande sambandet mellan CSR och earnings management i form av både AEM och REM. Resultaten är viktiga för företagens intressenter då de tyder på att högre CSR-engagemang inte är relaterat till mer etiskt agerande företagsledningar. Intressenterna bör främst vara vaksamma på aktiviteter som inte granskas av revisorer då dessa visats förekomma i högst utsträckning. Förslag till fortsatt forskning: I framtida studier kan sambandet mellan CSR och earnings management undersökas i företag där incitament till resultatmanipulation anses föreligga. Vidare kan ledningens syn på earnings management studeras mer ingående. Förslag ges även till att undersöka branschskillnader och att använda alternativa CSR-mått. / Aim: CSR is a highly topical and important subject for the companies and their stakeholders. Since higher CSR activities are considered to be related to ethically acting managements, this study investigates whether the management uses CSR as an attempt to conceal immoral activities in terms of earnings management. An opportunistic acting management uses earnings management to manipulate the result in the desired direction, which can be done through discretionary accruals (AEM) or through activities that affect the company’s cash flow (REM). Since these operates as substitutes, both are examined in the study. The study is based on Continental European companies where the application of law is based on civil law. These companies report according to IFRS and CSR reports according to GRI, which previous research pointed out as factors to affect the correlation between CSR and earnings management. The purpose of the study is therefore to investigate whether CSR is used as a means of concealing the existence of earnings management, and whether there is support for an opportunistic alternative ethical perspective. Method: The study has a quantitative research method and applies a positivistic research philosophy with a hypothetical-deductive approach. The study uses a cross-sectional design with secondary data from Continental European companies over a ten-year period (2008-2017). The data has been retrieved from Thomson Reuters Datastream and analyzed in IBM SPSS. Result & Conclusions: The results indicate that Continental European companies act opportunistically and uses CSR in attempts to hide earnings management. However, this can only be attributed to the REM activities abnormal cash flows and abnormal production costs. No relationship could be reported between CSR and AEM. Hence, it is concluded that it is important to study earnings management on the basis of both aspects to report fair results Contribution of the thesis: The study contributes to filling the research gap regarding the relationship between CSR and earnings management in both AEM and REM. The results are important for companies' stakeholders as they indicate that higher CSR involvement is not related to more ethical behavior of the company management. Stakeholders should primarily be vigilant on activities that are not audited by auditors as these have been shown to occur to the greatest extent. Suggestions for future research: In future studies, the relationship between CSR and earnings management can be investigated in companies where incentives for manipulation the financial performance are considered to exist. Furthermore, the management’s view of earnings management can be studied more thoroughly. Suggestions are also made to investigate industry differences and to use alternative CSR measures.
2

Defect microstructures, phase behavior and optical spectra of CoO-SnO2 ceramic composites

Pan, Ching-yu 20 July 2009 (has links)
none
3

Defect clusters, nanoprecipitates and Brownian motion of particles in Mg-doped Co1-xO, Ti-doped Co1-xO, Ti-doped MgO and Zr-doped TiO2

Yang, Kuo-Cheng 12 July 2005 (has links)
In part I, MgO and Co1-xO powders in 9:1 and 1:9 molar ratio (denoted as M9C1 and M1C9 respectively) were sintered and homogenized at 1600oC followed by annealing at 850 and 800oC, respectively to form defect clusters and precipitates. Analytical electron microscopic (AEM) observations indicated the protoxide remained as rock salt structure with complicated planar diffraction contrast for M9C1 sample, however with spinel paracrystal precipitated from the M1C9 sample due to the assembly of charge- and volume-compensating defects of the 4:1 type, i.e. four octahedral vacant sites surrounding one Co3+-filled tetrahedral interstitial site. The spacing of such defect clusters is 4.5 times the lattice spacing of the average spinel structure of Mg-doped Co3-dO4, indicating a higher defect cluster concentration than undoped Co3-dO4. The {111} faulting of Mg-doped Co3-dO4/Co1-xO in the annealed M1C9 sample implies the possible presence of zinc blend-type defect clusters with cation vacancies assembled along oxygen close packed (111) plane. In part II, the Mg2TiO4/MgO composites prepared by reactive sintering MgO and TiO2 powders (9:1 molar ratio) at 1600oC and then air-cooled or further aged at 900oC were studied by X-ray diffraction and (AEM) in order to characterize the microstructures and formation mechanism of nanosized Mg2TiO4 spinel precipitated from Ti-doped MgO. Expulsion of Ti4+ during cooling caused the formation of (001)-specific G.P. zone under the influence of thermal/sintering stress and then the spinel precipitates, which were about 30 nm in size and nearly spherical with {111} and {100} facets to minimize coherency strain energy and surface energy. Secondary nano-size spinel was precipitated and became site saturated during aging at 900oC, leaving a precipitate free zone at the grain boundaries of Ti-doped MgO. The intergranular spinel became progressively Ti-richer upon aging 900oC and showed <110>-specific diffuse scatter intensity likely due to short range ordering and/or onset decomposition. In part III, the Co1-xO/Co2TiO4 composite prepared by reactive sintering CoO and TiO2 powders (9:1 molar ratio) at 1450oC and then air-cooled were studied by X-ray diffraction and AEM in order to characterize the microstructures and formation mechanism of nanosized Co2TiO4 spinel precipitated from Ti-doped Co1-xO. Slight expulsion of Ti4+ during cooling caused the precipitation of nanosize Co2TiO4 spinel. Bulk site saturation also caused impingement of the Co2TiO4 precipitates upon growth. The Co3-dO4 spinel, as an oxidatin product of Co1-xO, was found to form at free surface and the Co1-xO/Co2TiO4 interface. The Co2TiO4 spinel particles formed by reactive sintering rather than precipitation were able to detach from the Co1-xO grain boundaries to reach parallel epitaxial orientation with respect to the host Co1-xO grains via Brownian-type rotation of the embedded particles. In part IV, AEM was used to study the defect microstructures of Zr-dissolved TiO2 prepared via reactive sintering the ZrO2 and TiO2 powders (8:92 in molar ratio, designated as Z8T92) at 1600oC for 24 h and then aged at 900oC for 2-200 h in air. The Zr-dissolved TiO2 with rutile structure showed dislocation arrays, defect clusters, G.P. zone, superlattice, nanometer-size domains incommensurate and commensurate superstructure, may be the precursor of ZrTi2O6 precipitates at 900oC. The rutile showed diffuse diffractions along [001] direction as a result of Zr4+ substitution for Ti4+ with volume compensating defect clusters. Incommensurate and commensurate structures, as indicated by diffraction splitting and extra diffraction along <100> and <010> directions may be attributed to the ordering and clustering process of Zr and Ti atoms in these directions. Part V, deals with the reactive sintering of ZrO2 and TiO2 powders (1:4 molar ratio) at 1400 to 1600oC in air to form orthorhombic ZrTiO4 (a-PbO2-type structure, denoted as a) and to study its epitaxial reorientation in the matrix of tetragonal TiO2 (rutile) grains with Zr4+ (15 mol %) dissolution. The epitaxial relationship of intragranular ZrTiO4 and Zr-dissolved rutile (denoted as r) was determined by electron diffraction as [010]a//[011]r; (001)a // (011)r (i.e. [100]a // [100]r; (001)a // (011)r). The reorientation of the intragranular particles in the composites can be reasonably explained by rotation of the nonepitaxial particles above a critical temperature (T/Tm > 0.8) and below a critical particle size for anchorage release at interface with respect to the host grain. Reactive sintering facilitated the reoreientation process for the particles about to detach from the grain boundaries. The Brownian rotation of the confined ZrTiO4 particles in rutile grains was activated by a beneficial lower interfacial energy for the epitaxial relationship, typically forming lath-like ZrTiO4 with (101)a/(211)r habit plane having fair match of oxygen atoms at the interface. Further aging at 900oC for 50 h in air caused modulated and periodic antiphase domains in ZrTiO4 matrix, as likely precursor of equilibrium ZrTi2O6.
4

Mechanistic understanding of Alloy 600 preferential intergranular oxidation : 'precursor events of stress corrosion cracking'

Bertali, Giacomo January 2016 (has links)
Primary Water Stress Corrosion Cracking (PWSCC) of Alloy 600 and similar Ni-Cr-Fe alloys is regarded as one of the most important challenges to nuclear power plant operation. During the past decades the majority of research has focused on PWSCC crack growth rate measurements in order to assess the lifetime of real components and to develop empirical models for crack propagation. However, the incubation and initiation stages of PWSCC have the same or even greater importance than the propagation stage, particularly because SCC can be undetected for more than 20 years before the occurrence of a rapid and catastrophic failure. There is, therefore, the scientific need to understand the mechanisms playing a fundamental role in the formation and development of intergranular cracks embryo, the so-called SCC initiation "precursor events", in order to be able to predict and mitigate the occurrence of PWSCC. Amongst all the models proposed for SCC initiation, the internal oxidation mechanism proposed by Scott and Le Calvar in 1992 appears to be the most comprehensive. Although the internal oxidation mechanism is widely accepted, it still requires further elucidation, especially in terms of enhanced grain boundary diffusivity and the role of intergranular carbides on the oxidation mechanism. The present work has focused on the initial stages of intergranular oxidation of solution-annealed (SA) and thermally-treated (TT) Alloy 600 with the aim of understanding the active mechanism responsible for the enhanced intergranular oxide penetration kinetics. The material was tested in simulated PWR primary water at 320°C, high-pressure hydrogenated-steam at 400°C and low-pressure H2-steam environment at 480°C at potential more reducing than the Ni/NiO equilibrium. The detailed microstructural characterization was conducted using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and analytical transmission electron microscopy (ATEM) and demonstrated that Alloy 600SA is susceptible to diffusion-induced grain boundary migration (DIGM), preferential intergranular oxidation (PIO) and localised Cr and Fe depletions at the grain boundaries. The similar analyses performed on Alloy 600TT demonstrated reduced susceptibility to PIO and grain boundary migration. Further, detailed analyses confirmed that intergranular carbides were readily oxidized/consumed in all 3 environments and acted as Cr reservoir/O trap. These results shed additional light on the "precursor events" for PWSCC of Alloy 600, especially on the mechanism responsible for the enhanced Cr and O diffusivity and on the mechanism responsible for the enhanced Alloy 600TT SCC initiation resistance. Moreover, the strong similarities in the Alloy 600 oxidation behaviour observed for the 3 different environments and at the 3 different temperatures suggested that the same PIO mechanism is active in both steam and water and at temperatures between 320°C and 480°C. These results strongly support the possibility of using the low-pressure H2-steam environment as a substitute environment to accelerate PWSCC initiation without changing the mechanism.
5

Management, methods and attitudes concerning grassland farming in Northern Germany

Hammes, Verena 03 February 2016 (has links)
No description available.
6

A Continuous Electrochemical Process to Convert Lignin to Low Molecular Weight Aromatic Compounds and Cogeneration of Hydrogen

Naderinasrabadi, Mahtab 02 June 2020 (has links)
No description available.
7

Component sizing in a microgrid with hydrogen as one energy carrier / Dimensionering av komponenter i ett mikronät med vätgas som enenergibärare

Strandberg, Josefin, Adolfsson, Erik, Jiang, Xiaoling, Zakko, Kresty January 2021 (has links)
En av de största utmaningarna framöver är att säkerställa en jämn övergång från fossila bränslen till förnybar energi utan att kompromissa driftstabilitet. För att genomföra detta behövs det någon form av energilagring för att lagra överskott av förnybar energi, exempelvis solenergi, som sedan kan användas när solenergin inte räcker till för att täcka elbehovet. Syftet med detta projektet är att modellera ett fristående mikronät med vätgaslagring i Simulink. Empiriska data har samlats för samtliga komponenter, som inkluderar en PEM bränslecell, ett NMC622 litiumjonbatteri och en AEM elektrolysör. På så sätt kunde ideala driftparametrar identifieras för komponenterna. Det modellerade systemet klarade elbehovet av en 2 W lampa för en hel vinter-, vår- och sommardag. Genom att använda väderdata för en vårdag kunde systemet dimensioneras för att uppfylla kravet för neutral balans med avseende på vätgasnivån och batteriernas laddningstillstånd. Det krävdes 38 solceller (med en total nominell effekt på 37.95 W), 5 batterier (med en total kapacitet av 175 mAh, 2 bränsleceller (med en vald effekt på 2.34 W inom det ohmiska intervallet) och 2 elektrolysörer (med en maximal effekt på 14.8504 W) för att uppfylla kravet. För att mikronätsystemet ska ha en större ekonomisk potential och en bättre genomförbarhet bör simuleringen förbättras genom att inkludera fler parametrar och använda väderdata som täcker längre perioder.
8

Patrons de distribution des crustacés planctoniques dans le fleuve Saint-Laurent

Cusson, Edith 04 1900 (has links)
La recherche porte sur les patrons de distribution longitudinale (amont-aval) et transversale (rive nord - rive sud) des communautés de crustacés planctoniques qui ont été analysés le long du fleuve Saint-Laurent entre le lac Saint-François et la zone de transition estuarienne, à deux hydropériodes en mai (crue) et en août (étiage). Les données zooplanctoniques et environnementales ont été récoltées à 52 stations réparties sur 16 transects transversaux en 2006. Au chapitre 1, nous présentons les principaux modèles écosystémiques en rivière, une synthèse des facteurs influençant le zooplancton en rivières et les objectifs et hypothèses de recherche. Au chapitre 2, nous décrivons la structure des communautés de zooplancton dans trois zones biogéographiques du fleuve et 6 habitats longitudinaux, ainsi que les relations entre la structure du zooplancton et la distribution spatiale des masses d’eau et les variables environnementales. Au chapitre 3, nous réalisons une partition de la variation des variables spatiales AEM (basées sur la distribution des masses d’eau) et des variables environnementales pour évaluer quelle part de la variation du zooplancton est expliquée par les processus hydrologiques (variables AEM) et les conditions locales (facteurs environnementaux). Le gradient salinité-conductivité relié à la discontinuité fleuve-estuaire a déterminé la distribution à grande échelle du zooplancton. Dans les zones fluviales, la distribution du zooplancton est davantage influencée par la distribution des masses d’eau que par les facteurs environnementaux locaux. La distribution des masses d’eau explique une plus grande partie de la variation dans la distribution du zooplancton en août qu’en mai. / The research aims to determine the distribution patterns of crustacean plankton along the longitudinal (west-east) and transversal (north shore - south shore) axes of the St. Lawrence River between Lake Saint-François and the estuarine transition zone, during two hydroperiods in May (high discharge) and August (low discharge). The zooplankton samples and the environmental data were collected at 52 stations distributed along 16 transversal transects in 2006. In chapter 1, we present the theoretical concepts of river ecosystem models, and a synthesis on the generative processes driving zooplankton spatial patterns in rivers. We also present our research objectives and hypotheses. In chapter 2, we describe spatial patterns of the zooplankton community structure in three biogeographic zones of the St. Lawrence and 6 longitudinal habitats, together with the relationships between zooplankton spatial structure and water masses spatial distribution and environmental characteristics. In chapter 3, we perform a variation partitioning procedure on spatial variables AEM (based on water masses spatial distribution) and environmental variables in order to assess how much of the zooplankton variation is explained by hydrological processes (AEM variables) and local conditions (environmental factors). The salinity-conductivity gradient related to the fluvial-estuary discontinuity determines the large-scale spatial patterns of the crustacean zooplankton. In the fluvial zones, the zooplankton distribution patterns are more influenced by the water masses spatial structure than by local environmental factors. The spatial distribution of the water masses explained more of the spatial structure of zooplankton communities in August than in May.
9

Impacts de l'urbanisation sur la diversité spécifique et fonctionnelle dans les forêts riveraines

Brice, Marie-Hélène 06 1900 (has links)
L'urbanisation représente une menace majeure pour la biodiversité. Ce mémoire de maîtrise vise à comprendre ses effets sur la composition fonctionnelle et l'homogénéisation biotique dans les forêts riveraines. Des inventaires floristiques ont été réalisés dans 57 forêts riveraines de la région de Montréal. Afin d'étudier la variation de la composition fonctionnelle avec l'urbanisation, des moyennes pondérées de traits par communauté ont été calculées pour les arbres, arbustes et herbacées. Chaque forêt a été caractérisée par des variables relatives au paysage urbain environnant, aux conditions locales des forêts et aux processus spatiaux. Les conditions locales, notamment les inondations, exerçaient une pression de sélection dominante sur les traits. L'effet du paysage était indirect, agissant via l'altération des régimes hydrologiques. La dispersion le long des rivières était aussi un processus important dans la structuration des forêts riveraines. Les changements dans la diversité β taxonomique et fonctionnelle des herbacées ont été étudiés entre trois niveaux d'urbanisation et d'inondation. Alors que l'urbanisation a favorisé une différenciation taxonomique, les inondations ont favorisé une homogénéisation taxonomique, sans influencer la diversité β fonctionnelle. L'urbanisation était l'élément déclencheur des changements de la diversité β, directement, en causant un gain en espèces exotiques et une diminution de la richesse totale dans les forêts très urbanisées, et, indirectement, en entraînant un important turnover d'espèces par l'altération des régimes hydrologiques. Globalement, ces résultats suggèrent que la modification des processus naturels par les activités anthropiques est le principal moteur de changements dans les communautés riveraines urbaines. / Urbanization is a major threat to biodiversity worldwide. This thesis aims at understanding its effects on plant functional composition and biotic homogenization in riparian forests. Floristic inventories were carried out in 57 riparian forests of the Montreal area. To investigate changes in functional composition with urbanization, community weighted means were computed for trees, shrubs and herbs using eight functional traits. Each forest was characterized by variables related to the surrounding urban landscape, local forest conditions and spatial processes. The relative importance of these three subsets on the functional composition was quantified by variation partitioning using redundancy analyses. Local conditions, especially flood intensity, exerted an overriding selection pressure on riparian functional communities. The effect of the landscape was suspected to be indirect, acting on trait patterns likely through alteration of hydrological disturbances in riparian forests. In addition to environmental filtering, dispersal along rivers was also an important process structuring riparian forests. Changes in taxonomic and functional β-diversity for herb species were studied between three urbanization and flood levels. While urbanization led to taxonomic differentiation, flood intensity fostered taxonomic homogenization, both without influence on functional β-diversity. Urbanization was the main trigger for all β-diversity changes, as it directly caused a gain in exotic species and a net species loss in highly urban forests, and indirectly fostered an important species turnover through alteration of the hydrological regime. Overall, these results suggest that the alteration and interruption of natural landscape-scale processes by human activities are major mechanisms underlying changes in urban riparian communities.
10

Patrons de distribution des crustacés planctoniques dans le fleuve Saint-Laurent

Cusson, Edith 04 1900 (has links)
La recherche porte sur les patrons de distribution longitudinale (amont-aval) et transversale (rive nord - rive sud) des communautés de crustacés planctoniques qui ont été analysés le long du fleuve Saint-Laurent entre le lac Saint-François et la zone de transition estuarienne, à deux hydropériodes en mai (crue) et en août (étiage). Les données zooplanctoniques et environnementales ont été récoltées à 52 stations réparties sur 16 transects transversaux en 2006. Au chapitre 1, nous présentons les principaux modèles écosystémiques en rivière, une synthèse des facteurs influençant le zooplancton en rivières et les objectifs et hypothèses de recherche. Au chapitre 2, nous décrivons la structure des communautés de zooplancton dans trois zones biogéographiques du fleuve et 6 habitats longitudinaux, ainsi que les relations entre la structure du zooplancton et la distribution spatiale des masses d’eau et les variables environnementales. Au chapitre 3, nous réalisons une partition de la variation des variables spatiales AEM (basées sur la distribution des masses d’eau) et des variables environnementales pour évaluer quelle part de la variation du zooplancton est expliquée par les processus hydrologiques (variables AEM) et les conditions locales (facteurs environnementaux). Le gradient salinité-conductivité relié à la discontinuité fleuve-estuaire a déterminé la distribution à grande échelle du zooplancton. Dans les zones fluviales, la distribution du zooplancton est davantage influencée par la distribution des masses d’eau que par les facteurs environnementaux locaux. La distribution des masses d’eau explique une plus grande partie de la variation dans la distribution du zooplancton en août qu’en mai. / The research aims to determine the distribution patterns of crustacean plankton along the longitudinal (west-east) and transversal (north shore - south shore) axes of the St. Lawrence River between Lake Saint-François and the estuarine transition zone, during two hydroperiods in May (high discharge) and August (low discharge). The zooplankton samples and the environmental data were collected at 52 stations distributed along 16 transversal transects in 2006. In chapter 1, we present the theoretical concepts of river ecosystem models, and a synthesis on the generative processes driving zooplankton spatial patterns in rivers. We also present our research objectives and hypotheses. In chapter 2, we describe spatial patterns of the zooplankton community structure in three biogeographic zones of the St. Lawrence and 6 longitudinal habitats, together with the relationships between zooplankton spatial structure and water masses spatial distribution and environmental characteristics. In chapter 3, we perform a variation partitioning procedure on spatial variables AEM (based on water masses spatial distribution) and environmental variables in order to assess how much of the zooplankton variation is explained by hydrological processes (AEM variables) and local conditions (environmental factors). The salinity-conductivity gradient related to the fluvial-estuary discontinuity determines the large-scale spatial patterns of the crustacean zooplankton. In the fluvial zones, the zooplankton distribution patterns are more influenced by the water masses spatial structure than by local environmental factors. The spatial distribution of the water masses explained more of the spatial structure of zooplankton communities in August than in May.

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