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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

Zinsschranke und EBITDA-Vortrag. Wirkungsanalyse unter Unsicherheit.

Baldauf, Thomas, Pummerer, Erich, Wittmann, Alexandra January 2010 (has links) (PDF)
(kein Abstract vorhanden) / Series: Discussion Papers SFB International Tax Coordination
2

Tax competition as a cause of falling corporate income taxes. A literature survey.

Hochgatterer, Claudia, Leibrecht, Markus January 2009 (has links) (PDF)
Tax rates on capital income, corporate income tax rates in particular, have been declining in most industrialized countries since the mid 1980ies. Among the explanations for this development tax competition between countries for mobile capital has been mentioned frequently. A vast empirical literature dealing with tax competition for mobile capital has emerged. This paper gives a comprehensive overview of these empirical studies. A particular focus is put on studies modelling strategic interaction in tax policies of competing jurisdictions - which is at the heart of the competition concept. The paper also addresses the issue whether existing studies convincingly isolate tax competition as a driver of falling capital / corporate income tax rates. Given the empirical evidence surveyed it appears that tax rates indeed fall due to tax competition, in particular due to competition for new firms and for paper profits. However, closer look at the empirical approaches applied in the papers surveyed suggests that fully convincing evidence establishing tax competition as driver of falling tax rates is still lacking. / Series: Discussion Papers SFB International Tax Coordination
3

Double J/u production at LHCb

Cook, Andrew David January 2015 (has links)
No description available.
4

Topikalisierung von attributiven Präpositionalphrasen im Deutschen

Briskina, Elena 19 December 2011 (has links)
Topikalisierung von attributiven Präpositionalphrasen stellt eine der Realisationsformen eines komplexen Wortstellungsphänomens des Deutschen dar, das in der Fachliteratur häufig als PP-Extraktion aus Nominalphrasen oder NP-PP-Aufspaltung bezeichnet wird. Sowohl Topikalisierung als auch weitere Realisationsformen der NP-PP-Aufspaltung unterliegen im Deutschen einer Reihe von strukturellen, lexikalisch-semantischen und pragmatischen Restriktionen, über die in der bisherigen Forschung bereits viel diskutiert wurde. Die Schwäche der bisherigen Ansätze besteht allerdings vor allem darin, dass die Daten aus dem authentischen Sprachgebrauch, wie z.B. Korpusdaten, in die Analyse kaum miteinbezogen wurden. Die empirische Basis der vorliegenden Untersuchung bildet dagegen eine umfangreiche Sammlung von Belegen, die aus einer Reihe von Korpora extrahiert wurden, die ihrerseits die gegenwärtigen Gebrauchstendenzen in der Standardsprache weitgehend repräsentieren (z.B. Zeitungs- und Nachrichtentexte, Parlamentsreden). Die Analyse des fraglichen Wortstellungsphänomens auf der Grundlage von Korpusdaten hat gezeigt, dass es sich dabei um ein viel komplexeres Phänomen handelt, als dies in der Forschung bislang angenommen wurde. Viele der bisherigen Annahmen über die strukturellen, lexikalisch-semantischen und pragmatischen Bedingungen der Topikalisierung von Präpositionalattributen im Deutschen erweisen sich als viel zu restriktiv. Vor allem zu den strukturellen Restriktionen lassen sich recht viele Gegenbeispiele finden. Eine stärkere Berücksichtigung von lexikalisch-semantischen Faktoren könnte dagegen zu einer adäquaten Erklärung dieses Wortstellungsphänomens des Deutschen, das vorwiegend durch Nomen-Verb-Verbindungen lizensiert wird, die Kollokationseigenschaften aufweisen, erheblich beitragen. / Topicalization of attributive prepositional phrases is a part of a complex word order phenomenon of German that is often referred to in the literature as PP-extraction from noun phrases or NP-PP-split. Topicalization, as well as the other forms of NP-PP-split in German, is due to a number of structural, lexical-semantic and pragmatic restrictions, which have already intensively been discussed in the literature. The weakness of the previous research is due to the fact that the data from the authentic language usage, for example corpus data, has been involved in the analysis to a very small extent. The empirical basis of this dissertation consists of a large collection of authentic sentences that have been extracted from some corpora of Standard German, which in turn can be treated as representative of the contemporary language usage (e.g. newspaper articles, online news and plenary protocols of the German Parliament). The analysis of this word order phenomenon on the basis of corpus data has shown that it is much more complex than previously believed. A number of the former hypotheses about structural, lexical-semantic and pragmatic conditions for the grammatical topicalization of prepositional attributes in German have turned out to be too restrictive. A lot of counter examples have been found, especially in regards to the structural restrictions discussed in some papers on NP-PP-split. Otherwise, a more intensive investigation of lexical-semantic factors could be useful for the adequate explanation of this word order phenomenon of German that seems usually to be licensed by noun-verb-combinations that can be considered collocations.
5

Bio-compatible coatings for bone implants.

Clearwater, Deborah Jayne January 2009 (has links)
Pulse Pressure Metal-Organic Chemical Vapour Deposition (PP-MOCVD) is a technique for creating thin coatings. It is less dependent on the volatility of precursors than other Chemical Vapour Deposition (CVD) processes as the precursors are introduced into the reaction chamber as an aerosol; therefore sublimation of the precursor is not necessary. This allows solutions of multiple compounds to be created with a known concentration and ratio of precursors. We explored the formation of hydroxyapatite (HAp) coatings for use on bone implants, using a methanolic solution of calcium lactate and trimethyl phosphate (TMP) as a PP-MOCVD precursor solution. The thermal decomposition of the precursors and the reaction between them were investigated using Thermogravimetric Analysis (TGA). Several variables on the PP-MOCVD apparatus were varied to test their effect on the formed coating: deposition temperatures, ratio of precursors, number of pulses, precursor concentration, the use of ambient temperatures and annealing the coatings after formation. All the coatings were analysed using Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS) and Fourier Transform Infra-Red spectroscopy (FTIR). These coatings were not uniformly smooth in appearance at the micro level. However, using higher deposition temperatures, an excess ratio of TMP to calcium lactate and annealing the coatings for short periods of time and low temperatures improved the uniformity of the coating. When vigorous annealing was performed it resulted in surface oxidation and the production of titanium dioxide (TiO2 ). The EDS results showed that both calcium and phosphorus were present in the coatings. The use of high deposition temperatures, excess TMP or gentle annealing resulted in calcium to phosphorous ratios similar to the stoichiometry of HAp. These same conditions gave improved coating uniformity.
6

Development of Modelling Techniques for Pulsed Pressure Chemical Vapour Deposition (PP-CVD)

Cave, Hadley Mervyn January 2008 (has links)
In this thesis, a numerical and theoretical investigation of the Pulsed Pressure Chemical Vapour Deposition (PP-CVD) progress is presented. This process is a novel method for the deposition of thin films of materials from either liquid or gaseous precursors. PP-CVD operates in an unsteady manner whereby timed pulsed of the precursor are injected into a continuously evacuated reactor volume. A non-dimensional parameter indicating the extent of continuum breakdown under strong temporal gradients is developed. Experimental measurements, supplemented by basic continuum simulations, reveal that spatio-temporal breakdown of the continuum condition occurs within the reactor volume. This means that the use of continuum equation based solvers for modelling the flow field is inappropriate. In this thesis, appropriate methods are developed for modelling unsteady non-continuum flows, centred on the particle-based Direct Simulation Monte Carlo (DSMC) method. As a first step, a basic particle tracking method and single processor DSMC code are used to investigate the physical mechanisms for the high precursor conversion efficiency and deposition uniformity observed in experimental reactors. This investigation reveals that at soon after the completion of the PP-CVD injection phase, the precursor particles have an approximately uniform distribution within the reactor volume. The particles then simply diffuse to the substrate during the pump-down phase, during which the rate of diffusion greatly exceeds the rate at which particles can be removed from the reactor. Higher precursor conversion efficiency was found to correlate with smaller size carrier gas molecules and moderate reactor peak pressure. An unsteady sampling routine for a general parallel DSMC method called PDSC, allowing the simulation of time-dependent flow problems in the near continuum range, is then developed in detail. Nearest neighbour collision routines are also implemented and verified for this code. A post-processing procedure called DSMC Rapid Ensemble Averaging Method (DREAM) is developed to improve the statistical scatter in the results while minimising both memory and simulation time. This method builds an ensemble average of repeated runs over small number of sampling intervals prior to the sampling point of interest by restarting the flow using either xi a Maxwellian distribution based on macroscopic properties for near equilibrium flows (DREAM-I) or output instantaneous particle data obtained by the original unsteady sampling of PDSC for strongly non-equilibrium flows (DREAM-II). The method is validated by simulating shock tube flow and the development of simple Couette flow. Unsteady PDSC is found to accurately predict the flow field in both cases with significantly reduced run-times over single processor code and DREAM greatly reduces the statistical scatter in the results while maintaining accurate particle velocity distributions. Verification simulations are conducted involving the interaction of shocks over wedges and a benchmark study against other DSMC code is conducted. The unsteady PDSC routines are then used to simulate the PP-CVD injection phase. These simulations reveal the complex flow phenomena present during this stage. The initial expansion is highly unsteady; however a quasi-steady jet structure forms within the reactor after this initial stage. The simulations give additional evidence that the collapse of the jet at the end of the injection phase results in an approximately uniform distribution of precursor throughout the reactor volume. Advanced modelling methods and the future work required for development of the PP-CVD method are then proposed. These methods will allow all configurations of reactor to be modelled while reducing the computational expense of the simulations.
7

The preparation and characterization of polypropylene-compatibilizer-filler composites

Huang, Huan Yao, barbar0324@gmail.com January 2010 (has links)
Polypropylene (PP) composites includ a mineral filler, though they can be enhanced by blending with an elastomer. Blending rigid fillers with PP increased strength while decreasing toughness. Blending soft elastomers with PP decreased strength while increasing toughness. PP-elastomer-filler ternary composites offer synergism because the increase of strength due to filler may compensate the loss of strength due to the elastomer. Two morphologies were identified, separated elastomer and filler particles in PP, and filler particles encapsulated by elastomer in PP. Interaction between filler and PP matrix are proposed to increase with the addition of polar elastomers when encapsulated morphology is formed, leading to enhanced mechanical properties. PP-elastomer-filler blended tapes were prepared via single-screw extrusion. Annealing was performed after cooling the tapes, and this combination proved to increase the modulus. Characterization of the composites was carri ed out using thermogravimetry, dynamic-force thermomechanometry, modulated-force thermomechanometry, and Fourier transform infrared imaging. Incorporation of polysiloxane elastomer increased the mobility of PP during extrusion. Elongation at break increased with increasing polysiloxane content, while the tensile modulus was slightly decreased. The silica core within the polysiloxane particles provided an additional strength enhancement. Polar elastomers aided binding between PP and fillers, while enhancing strength and toughness. Glass transition temperature and segmental motion activation energy was shifted to higher temperature with addition of elastomer and filler, including kaolin and talc.
8

Bio-compatible coatings for bone implants.

Clearwater, Deborah Jayne January 2009 (has links)
Pulse Pressure Metal-Organic Chemical Vapour Deposition (PP-MOCVD) is a technique for creating thin coatings. It is less dependent on the volatility of precursors than other Chemical Vapour Deposition (CVD) processes as the precursors are introduced into the reaction chamber as an aerosol; therefore sublimation of the precursor is not necessary. This allows solutions of multiple compounds to be created with a known concentration and ratio of precursors. We explored the formation of hydroxyapatite (HAp) coatings for use on bone implants, using a methanolic solution of calcium lactate and trimethyl phosphate (TMP) as a PP-MOCVD precursor solution. The thermal decomposition of the precursors and the reaction between them were investigated using Thermogravimetric Analysis (TGA). Several variables on the PP-MOCVD apparatus were varied to test their effect on the formed coating: deposition temperatures, ratio of precursors, number of pulses, precursor concentration, the use of ambient temperatures and annealing the coatings after formation. All the coatings were analysed using Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS) and Fourier Transform Infra-Red spectroscopy (FTIR). These coatings were not uniformly smooth in appearance at the micro level. However, using higher deposition temperatures, an excess ratio of TMP to calcium lactate and annealing the coatings for short periods of time and low temperatures improved the uniformity of the coating. When vigorous annealing was performed it resulted in surface oxidation and the production of titanium dioxide (TiO2 ). The EDS results showed that both calcium and phosphorus were present in the coatings. The use of high deposition temperatures, excess TMP or gentle annealing resulted in calcium to phosphorous ratios similar to the stoichiometry of HAp. These same conditions gave improved coating uniformity.
9

A histological analysis of the role of a LOX-PP variant in breast cancer, leukemia, and lymphoproliferative disease

Emmerling, Michael John 17 June 2016 (has links)
BACKGROUND: In their lifetime, 42% of men and 38% of women will be diagnosed with cancer. One of the most prominent cancers in women is breast cancer, which represents 14.8% of newly diagnosed cancers. Research has demonstrated the importance of the lysyl oxidase (LOX) gene, more specifically the lysyl oxidase propeptide (LOX-PP), in the attenuation of breast cancer and in mouse xenograft models, making it an important and ongoing area of investigation. In recent, unpublished experiments, mice with a variant of LOX-PP were treated with 7,12-Dimethylbenz[a]anthracene (DMBA) to induce breast cancer. However, some of the treated mice developed poor body conditions without any signs of having developed breast cancer. Published studies have demonstrated that, following treatment with DMBA, some mice generate leukemia or other lymphoproliferative diseases. Research has shown that identification of these diseases is possible via histological analyses or immunohistochemistry. Objective: To determine the cause of poor body conditions in mice treated with DMBA that did not develop mammary tumors by histological analyses and immunohistochemistry. Additionally, to determine the difference between a variant of LOX-PP (LOX-PPv) knock-in (Ki) and wild type (WT) mice in the generation of poor body conditions or leukemia/lymphoproliferative disease. METHODS: A total of 48 mice, 24 LOX-PPv Ki and 24 WT, were treated with DMBA and observed for mammary tumor formation. Body conditions of the mice were observed and noted, and liver samples from these mice were obtained and analyzed via histological and immunohistochemistry interventions. In Hematoxylin & Eosin (H&E) assessments of mice livers, mice were classified as normal or as having possible lymphocyte infiltration, mild lymphocyte infiltration, or massive lymphocyte infiltration. Staining with the Ki-67 antibody in immunohistochemistry allowed for classification of mouse livers as normal or as having slightly positive or massively positive expression of the Ki-67 antigen. The degree to which each liver sample was positive for both readings was compared and further analyzed. RESULTS: A total of 9 mice (30.4% of Ki mice and 8.7% of WT mice) displayed poor body conditions following DMBA treatment. Of the 9 (7 Ki and 2 WT) mice having poor body condition, 2 Ki mice suffered from severe dermatitis. For the 7 remaining mice, no cause for such poor body conditions was obvious. 6 of these mice (85.7%) were diagnosed with leukemia. In all other DMBA-treated mice, 52.6% of Ki and 23.8% of WT displayed some degree of abnormal lymphocyte infiltration in the liver, while a total of 39.1% of the K¬I mice and 69.6% of the WT mice had normal liver histologies. 60.9% of Ki and 45.5% of WT mice displayed some degree of positivity for expression of Ki-67. CONCLUSIONS: Mice not diagnosed with breast cancer but that were suffering from poor body conditions likely had developed leukemia or some other lymphoproliferative disease. In the mice not definitively diagnosed with leukemia by a pathologist, H&E analyses and immunohistochemistry of the livers showed lymphocyte infiltration and cellular proliferation possibly indicative of leukemia., but further tests are necessary to confirm this. Furthermore, LOX-PPv Ki mice appeared to have a greater likelihood of generating poor body conditions or some observable sign of abnormal lymphocyte infiltration in the liver versus their WT counterparts when treated with DMBA. / 2018-06-16T00:00:00Z
10

Strengthening masonry for seismic actions in developing countries

Ali, Ather January 2017 (has links)
The study presented aims to provide the most viable seismic retrofit solution for rural masonry. Muzffarabad is one such region where excess of unreinforced masonry structures claimed thousands of lives during 2005 earthquake. Field study was conducted in the region to familiarize with the dynamics of local construction industry before suggesting a suitable retrofit solution. Polypropylene (PP-) band retrofit has been selected as the most viable solution for retrofitting existing masonry structures in terms of cost, material availability and ease of application. To prove the efficiency of PP-band retrofit, numerical simulations and laboratory tests were conducted to assess the seismic efficiency of PP-band retrofit. Material tests were conducted in accordance with BS-EN to familiarize with the mechanical properties of locally available materials in Kashmir region and to provide material data for numerical analysis. Tests revealed lower strength and elasticity for bricks in comparison to materials found in developed countries, due to the unregulated and non-standardized manufacturing of masonry units and high water content in mortars. Shake table tests were conducted to test the effectiveness of PP-band retrofit masonry under dynamic vibrations. Results show that PP-band retrofit can enhance the post peak performance by at least 7 times in comparison to non-retrofit specimen. Real-scale structure retrofit with PP-band survived accelerations of up to 2g without any life-threatening damage, thus, proving to be an economic and efficient strengthening solution for rural communities. Following the shortcomings observed in Room-1, connection detail for PP-bands in Room-2 was revised to achieve a 100% performance enhancement. Numerical models were developed to predict cracks in masonry and analyse diagonal compression test models, in accordance with ASTM standards. The results showed 30% higher residual strength after cracking for PP- band retrofit masonry and the wall integrity was maintained for higher deformations.

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