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Advertising, Performance and Mutual Fund Flows: The Allocation Proportion for Advertising of FundsWei, An-Pin 09 January 2012 (has links)
Prior studies have found that a firm advertising for one of its products not only can increase the sales of the advertised product, but also spill over the advertising effect by increasing sales of other existing products in the same brand. This study examines whether a fund family spending money on one of its managed funds can attract more money flows into the advertised fund and bring the advertising spillover effect that attract more money flows into other members in the same family. Under the assumption that a fund family is a risk aversion investor endowed with a negative exponential utility function, this study finds a theoretical allocation proportion for a fund family¡¦s spending on advertising of individual funds under management, which is the function of the fund family¡¦s risk aversion level and initial wealth, as well as the mean and the variance of the expected returns generated by individual funds¡¦ advertising and the advertising spillover effect. Empirically, the evidence shows that an advertised fund can significantly attract greater cash flows and bring the significant advertising spillover effect on cash flows of other individual funds in the same family. After grouping funds into lower-, mid- and higher-performing funds based on funds¡¦ past performance, the results indicate that an advertised fund with mid performance can attract greater cash flows than an advertised fund with higher and lower performance. Moreover, an advertised fund can bring stronger advertising spillover effect on cash flows of higher-performing funds than lower- and mid-performing funds in the same family. Regarding with the family cash flows, the evidence shows that a fund family¡¦s aggregating advertising expenditures on managed funds can significantly increase the family cash flows and the advertising effect on the family cash flows is stronger in large families than in small families. The empirical results suggest that a fund family can benefit from its advertising expenditures and which allocating higher proportion for advertising of mid-performing funds than higher-performing funds could attract money flows into its managed funds more efficiently.
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Investigation of Swirl Flows Applied to the Oil and Gas IndustryRavuri Venkata Krish, Meher Surendra 16 January 2010 (has links)
Understanding how swirl flows can be applied to processes in the oil and gas industry and how problems might hinder them, are the focus of this thesis. Three application areas were identified: wet gas metering, liquid loading in gas wells and erosion at pipe bends due to sand transport. For all three areas, Computational Fluid Dynamics (CFD) simulations were performed. Where available, experimental data were used to validate the CFD results. As a part of this project, a new test loop was conceived for the investigation of sand erosion in pipes.
The results obtained from CFD simulations of two-phase (air-water) flow through a pipe with a swirl-inducing device show that generating swirl flow leads to separation of the phases and creates distinct flow patterns within the pipe. This effect can be used in each of the three application areas of interest.
For the wet gas metering application, a chart was generated, which suggests the location of maximum liquid deposition downstream of the swirling device used in the ANUMET meter. This will allow taking pressure and phase fraction measurements (from which the liquid flow rate can be determined) where they are most representative of the flow pattern assumed for the ANUMET calculation algorithms.
For the liquid loading application, which was taken as an upscaling of the dimensions investigated for the wet gas metering application, the main focus was on the liquid hold-up. This parameter is defined as the ratio of the flowing area occupied by liquid to the total area. Results obtained with CFD simulations showed that as the water rate increases, the liquid hold-up increases, implying a more effective liquid removal. Thus, it was concluded that the introduction of a swirler can help unload liquid from a gas well, although no investigation was carried out on the persistance of the swirl motion downstream of the device.
For the third and final application, the erosion at pipe bends due to sand transport, the main focus was to check the erosion rate on the pipe wall with and without the introduction of a swirler. The erosion rate was predicted by CFD simulations. The flow that was investigated consisted of a liquid phase with solid particles suspended in it. The CFD results showed a significant reduction in erosion rate at the pipe walls when the swirler was introduced, which could translate into an extended working life for the pipe. An extensive literature review performed on this topic, complemented by the CFD simulations, showed the need for a dedicated multiphase test loop for the investigation of sand erosion in horizontal pipes and at bends. The design of a facility of this type is included in this thesis.
The results obtained with this work are very encouraging and provide a broad perspective of applications of swirl flows and CFD for the oil and gas industry.
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Experimental and Numerical Study of Molecular Mixing Dynamics in Rayleigh- Taylor Unstable FlowsMueschke, Nicholas J. 16 January 2010 (has links)
Experiments and simulations were performed to examine the complex processes that
occur in Rayleigh�Taylor driven mixing. A water channel facility was used to examine
a buoyancy-driven Rayleigh�Taylor mixing layer. Measurements of �uctuating den-
sity statistics and the molecular mixing parameter were made for Pr = 7 (hot/cold
water) and Sc 103 (salt/fresh water) cases. For the hot/cold water case, a high-
resolution thermocouple was used to measure instantaneous temperature values that
were related to the density �eld via an equation of state. For the Sc 103 case, the
degree of molecular mixing was measured by monitoring a di�usion-limited chemical
reaction between the two �uid streams. The degree of molecular mixing was quanti-
�ed by developing a new mathematical relationship between the amount of chemical
product formed and the density variance 02. Comparisons between the Sc = 7 and
Sc 103 cases are used to elucidate the dependence of on the Schmidt number.
To further examine the turbulent mixing processes, a direct numerical simu-
lation (DNS) model of the Sc = 7 water channel experiment was constructed to
provide statistics that could not be experimentally measured. To determine the key
physical mechanisms that in�uence the growth of turbulent Rayleigh�Taylor mixing
layers, the budgets of the exact mean mass fraction em1, turbulent kinetic energy fE00,
turbulent kinetic energy dissipation rate e 00, mass fraction variance gm002
1 , and mass
fraction variance dissipation rate f 00 equations were examined. The budgets of the unclosed turbulent transport equations were used to quantitatively assess the relative
magnitudes of di�erent production, dissipation, transport, and mixing processes.
Finally, three-equation (fE00-e 00-gm002
1 ) and four-equation (fE00-e 00-gm002
1 -f 00) turbulent
mixing models were developed and calibrated to predict the degree of molecular mix-
ing within a Rayleigh�Taylor mixing layer. The DNS data sets were used to assess
the validity of and calibrate the turbulent viscosity, gradient-di�usion, and scale-
similarity closures a priori. The modeled transport equations were implemented in a
one-dimensional numerical simulation code and were shown to accurately reproduce
the experimental and DNS results a posteriori. The calibrated model parameters
from the Sc = 7 case were used as the starting point for determining the appropri-
ate model constants for the mass fraction variance gm002
1 transport equation for the
Sc 103 case.
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The Determinants Of Capital Flows: The Turkish EvidenceKara, Serdar Ufuk 01 September 2007 (has links) (PDF)
This study investigates the domestic and external determinants of net capital flows to Turkey. The results of the Johansen cointegration analyses indicate that capital flows to Turkey increase in response to increases in domestic real interest rate, domestic real income growth, and budget balance / appreciation of domestic currency / and decreases in financial fragility and the US real interest rates. It can be said that, higher domestic real returns and improved country creditworthiness attract more foreign capital flows to Turkey. In addition, the decreases in world interest rates enable Turkey to enjoy higher capital flows. The findings are theory consistent and data-acceptable.
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Development Of De-icing And Anti-icing Solutions For Aircraft On Ground And Analysis Of Their Flow Instability CharacteristicsKorpe, Durmus Sinan 01 September 2008 (has links) (PDF)
In this thesis, development process of de-icing and anti-icing solutions and their flow instability characteristics are presented.
In the beginning, the chemical additives in the solutions and their effects on the most critical physical properties of the solutions were investigated. Firstly, chemical additives were added to glycol and water mixtures at different weight ratios one by one in order to see their individual effects. Then, the changes in physical properties were observed when the chemicals were added to water-glycol mixture together. After that, study was focused on effect of polymer which makes the solution pseudoplastic. Further investigations on viscosity behavior of the solution at different pH values, glycol and water mixtures and surfactant weight ratios, which is used for surface tension reduction, were performed.
For the investigation of flow instability characteristics of the solutions&rsquo / flows, linear stability analysis for two-layer flows is a basic tool. Firstly, the effects of main parameters on the stability of two-layer flows were observed with a parametric study. Then, the commercially available and developed de-icing and anti-icing solutions were compared according to the characteristics of unstable waves. According to the results, unstable waves on developed de-icing fluids are observed at a lower critical wind speed compared to the commercially available de-icing solution. Moreover, it flows off the wing faster due to a higher value of critical wave speed. Developed anti-icing solution has similar wave characteristics compared to commercially available anti-icing solution, except critical wave speed, which is significantly lower. However, this problem can be overcome by decreasing the viscosity of developed anti-icing solution at very low shear rates.
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The Determinants Of Portfolio Investments To Turkey: From 1989 To 2008Gunayer, Elif 01 November 2009 (has links) (PDF)
This thesis analyzes the factors that determine the portfolio investments to Turkey in the period from 1989:04 to 2008:12. The factors that are examined are budget balance, current account balance, nominal exchange rate between the Turkish Lira and the US dollar, Turkish domestic interest rate, US 3-months Treasury Bill rate, annual inflation rate in Turkey and ISE 100 Index. A Vector Autoregressive Model is used for the purpose of examining the impacts of these variables on the level of portfolio investments to Turkey. The results of the model show that the portfolio investment in Turkey was affected positively by domestic interest rates and negatively by ISE 100 Index in the period before 2001. On the other hand, it is affected positively by exchange rate and US interest rate in the post-crisis period. It is also found that current account deficit affect portfolio investments negatively.
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Effect of harmonic forcing on turbulent flame propertiesThumuluru, Sai Kumar 15 November 2010 (has links)
Lean premixed combustors are highly susceptible to combustion instabilities, caused by the coupling between heat release fluctuations and combustor acoustics. In order to predict the conditions under which these instabilities occur and their limit cycle amplitudes, understanding of the amplitude dependent response of the flame to acoustic excitation is required. Extensive maps of the flame response were obtained as a function of perturbation amplitude, frequency, and flow velocity. These maps illustrated substantial nonlinearity in the perturbation velocity - heat release relationship, with complex topological dependencies that illustrate folds and kinks when plotted in frequency-amplitude-heat release space. A detailed analysis of phase locked OH PLIF images of acoustically excited swirl flames was used to identify the key controlling physical processes and qualitatively discuss their characteristics. The results illustrate that the flame response is not controlled by any single physical process but rather by several simultaneously occurring processes which are potentially competing, and whose relative significance depends upon forcing frequency, amplitude of excitation, and flame stabilization dynamics. An in-depth study on the effect of acoustic forcing on the turbulent flame properties was conducted in a turbulent Bunsen flame using PIV measurements. The results showed that the flame brush thickness and the local consumption speed were modulated in the presence of acoustic forcing. These results will not only be a useful input to help improve combustion dynamics predictions but will also help serve as validation data for models.
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Substrate effects from force chain dynamics in dense granular flowsEstep, Joseph Jeremiah 05 April 2011 (has links)
Granular materials are composed of solid, discrete particles and exhibit mechanical behavior that differs from those of fluids and solids. The rheology of granular flows is principal to a suite of natural hazards. Laboratory experiments and numerical models have adequately reproduced several features observed in terrestrial gravity driven geophysical flows; however, quantitative comparison to field observations exposes a failure to explain the high mobility and duration of many of these flows. The ability of a granular material to resist deformation is a function of the force chain network inherent to the material. This investigation addresses the evolutionary character of force chains in unconfined, two-dimensional, gravity driven granular flows. Our particular emphasis concerns the effects of stress localization on the substrate by dynamic force chain evolution and the implications for bed erosion in dense granular flows. Experimental systems employing photoelastic techniques provide an avenue for quantitative force analysis via image processing and provide dataset that can be used validate discrete element modeling approaches. We show that force chains cause extreme bed force localization throughout dynamic granular systems in spatial and temporal space; and that these localized forces can propagate extensively into the substrate, even ahead of the flow front.
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Transportation resource management in large-scale freight consolidation networksCarbajal Orozco, Jose Antonio 24 August 2011 (has links)
This dissertation proposes approaches that enable effective planning and control of mobile transportation resources in large-scale consolidation networks. We develop models, algorithms, and methodologies that are applied to fleet sizing and fleet repositioning. Three specific but interrelated problems are studied. The first two relate to the trade-offs between fleet size and repositioning costs in transportation resource management, while the third involves a dynamic empty repositioning problem with explicit consideration of the uncertainty of future requirements that will be revealed over time.
Chapter 1 provides an overview of freight trucking, including the consolidation trucking systems that will be the focus of this research.
Chapter 2 proposes an optimization modeling approach for analyzing the trade-off between the cost of a larger fleet of tractors and the cost of repositioning tractors for a trucking company operating a consolidation network, such as a less-than-truckload (LTL) company. Specifically, we analyze the value of using extra tractor repositioning moves (in addition to the ones required to balance resources throughout the network) to attain savings in the fixed costs of owning or leasing a tractor fleet during a planning horizon. The primary contributions of the research in this chapter are that (1) we develop the first optimization models that explore the impact of fleet size reductions via repositioning strategies that have regularity and repeatability properties, and (2) we demonstrate that substantial savings in operational costs can be achieved by repositioning tractors in anticipation of regional changes in freight demand.
Chapter 3 studies the optimal Pareto frontiers between the fleet size and repositioning costs of resources required to perform a fixed aperiodic or periodic schedule of transportation requests. We model resource schedules in two alternative ways: as flows on event-based, time-expanded networks; and as perfect matchings on bipartite networks. The main contributions from this chapter are that (1) we develop an efficient re-optimization procedure to compute adjacent Pareto points that significantly reduces the time to compute the entire Pareto frontier of fleet size versus repositioning costs in aperiodic networks, (2) we show that the natural extension to compute adjacent Pareto points in periodic networks does not work in general as it may increase the fleet size by more than one unit, and (3) we demonstrate that the perfect matching modeling framework is frequently intractable for large-scale instances.
Chapter 4 considers robust models for dynamic empty-trailer repositioning problems in very large-scale consolidation networks. We investigate approaches that deploy two-stage robust optimization models in a rolling horizon framework to address a multistage dynamic empty repositioning problem in which information is revealed over time. Using real data from a national package/parcel express carrier, we develop and use a simulation to evaluate the performance of repositioning plans in terms of unmet loaded requests and execution costs. The main contributions from this chapter are that (1) we develop approaches for embedding two-stage robust optimization models within a rolling horizon framework for dynamic empty repositioning, (2) we demonstrate that such approaches enable the solution of very large-scale instances, and (3) we show that less conservative implementations of robust optimization models are required within rolling horizon frameworks.
Finally, Chapter 5 summarizes the main conclusions from this dissertation and discusses directions for further research.
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The Effect of Environmental Regulations on Trade Flows : A Study of the European Union / Hur Handelsflöden Påverkas av Miljöregulationer : En Studie av den Europeiska UnionenFransson, Sara, Emanuelsson, Ida January 2006 (has links)
<p>The purpose of this thesis is to investigate if the trade flows within the European Union are affected by the environmental policies within the union. An environmental sensitivity index (IESP) is used as explanatory variable, with export and import shares respectively as dependent variables. The trade flow data is collected from the OECD database for the years 1995 to 1998, and is used in a regression analysis together with IESP data from the same years. The analysis covers 15 European Union member countries. The result from the regression analysis shows a positive relationship between IESP and trade flows. However, our values did not turn out to be significant, much due to the low number of observations and too few explanatory variables.</p> / <p>Syftet med denna uppsats är att undersöka om handelsflödena inom den Europeiska Unionen påverkas av miljöpolitiken inom unionen. Ett index som mäter miljökänslighet (IESP) används som förklarande variabel, med export respektive import som beroende variabler. Data om handelsflöden är hämtade från OECDs databas och täcker åren 1995-1998. Dessa data används i en regressionsanalys tillsammans med IESP data från samma period. Analysen täcker 15 medlemsländer från den Europeiska Unionen. Resultaten från regressionsanalysen pekar på ett positivt samband mellan handelsflöden och IESP. Tyvärr blev våra värden ej signifikanta, mycket beroende på för få observationer och förklarande variabler.</p>
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