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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.
141

Optimal Capacity Investment, and Pricing Across International Markets Under Exchange Rate Uncertainty and Duopoly Competition

Ahmed, Anas A. 11 May 2010 (has links)
In this dissertation we investigate joint optimal capacity investment, pricing and production decisions for a multinational manufacturer who faces exchange rate uncertainties. We consider a manufacturer that sells its product in both domestic and foreign markets over a multiperiod season. Because of long-lead times, the capacity investment must be committed before the selling season begins. The exchange rate between the two countries fluctuates across period and the demand in both markets is price dependent. In the first part, the model considers three scenarios: (1) early commitment to price and quantity with central sourcing, (2) postponement of prices and quantities with central sourcing, and (3) local sourcing. We derive the optimal capacity and the optimal prices for each scenario, and investigate the impact of the exchange rate parameters and the length of the selling season on optimal capacity investment, production allocation, and pricing decisions. We observe that while the price and production decisions in the domestic market are independent of the exchange rate under early commitment and local sourcing scenarios, the exchange rate between two countries directly impacts these decisions under the postponement setting. We identify thresholds and gain insights on investment costs, market potentials, exchange rate drifts, and selling season length for the choice of entering a foreign market under all scenarios. In the second part of this dissertation, we consider a duopoly competition in the foreign country. We consider a single period setting and we model the exchange rate as a random variable. We assume two scenarios: (1) Exogenous Model, where the price of the foreign manufacturer is set a priori, and (2) Endogenous Model, where the prices are set simultaneously based on a Nash Game outcome. In the Exogenous Model, we study the impact of exchange rate and foreign manufacturer's price on optimal capacity and prices. In the Endogenous Model, we investigate the impact of competition and exchange rate on optimal capacities and optimal prices. We show how competition can impact the decision of the home manufacturer to enter the foreign market.
142

Essays in the study and modelling of exchange rate volatility

Sucarrat, Genaro 28 September 2006 (has links)
The thesis is a contribution to the literature on the study and modelling of exchange rate variability, and contains seven chapters. Chapter 1 motivates the study by providing a historical context about its importance, sketches the main themes of the thesis, and gives an overview of the Norwegian economy since the empirical studies are on the Norwegian krone against the Euro exchange rate. Chapter 2 makes a distinction between period and within-period exchange rate variability, a distinction which is of special interest when studying variability across different exchange rate regimes. Also, the exponential model of variability (EMOV) is put forward as a particularly convenient framework for explanatory exchange rate variability modelling. Chapter 3 makes full fuse of these ideas in studying the impact of market activity on exchange rate variability in the case of Norway. The main findings of this study are that the impact of short-term change in market activity, as measured by relative week-to-week changes in quoting frequency, is positive and statistically significant for both definitions of variability, and that the impact is relatively stable across three different exchange rate regimes. Also, our results do not suggest that the persistence in variability can be explained by persistence in the level of quoting. Chapter 4 undertakes an out-of-sample forecast evaluation of general to specific (GETS) modelling of exchange rate volatility, and our results suggest GETS-derived models are particularly useful in conditional forecasting. Chapter 5 studies the relation between exchange rate variability, market activity and heterogeneity using a measure of spot NOK/EUR transaction volume from banks within Norway's regulatory borders. Our results do not support the hypothesis that short-term Norwegian market activity has an impact on variability. However, we do find some support of the hypothesis that large and small banks have an opposite impact through their long-term activity. Chapter 6 proposes a solution to a shortcoming in the first stage of David F. Hendry's reduction theory by interpreting the underlying outcome space as a set of possible worlds made up of indeterministic and historically inherited particulars. Finally, chapter 7 concludes and provides suggestions for further research.
143

Simulated plume development and decommissioning using the breakthrough curves of five cations

Rinas, Crystal Dawn 11 July 2011
The primary objective of this research was to investigate multicomponent transport of five major cations, Ca2+, Mg2+, NH4+, K+ and Na+, in laboratory soil columns. The soil columns were packed with soils from two different sites and were equilibrated with fresh groundwater from each respective site. Experimental data was obtained by flushing a simulated contaminant through the soil columns. The soil columns were then flushed with fresh groundwater to simulate decommissioning activities. The breakthrough data and soil exchange capacities obtained from both tests were used to identify key processes affecting the transport of the geochemical species. During the simulated contaminant flushing stage, NH4+ and K+ replaced Ca2+ and Mg2+ on the soil exchange sites. Breakthrough of NH4+ was attenuated by factors of 3.2 and 6 for Sites 1 and 2 soils, respectively. Breakthrough of K+ was attenuated by factors of 3.2 and 5.4 for Sites 1 and 2 soils, respectively. Generally, ions with higher valency will exchange for those of lower valency, but in this case the majority of the ions (NH4+ and K+) in the solution has a lower valency and will exchange with those of higher valency by mass action. Ca2+ was the first to be replaced, followed by Mg2+ once the ionic strength of the solution increased. The displacement of calcium and magnesium created a concentration pulse of these cations that coincides with the chloride breakthrough curve. Calcium and magnesium concentrations reached up to approximately 275% and 2000%, respectively, higher than the freshwater originally in the column. During the freshwater flushing stage, freshwater infiltrated the soil columns to assess the permanency of contaminant attenuation and to identify the geochemical mechanisms of contaminant release. Concentrations of NH4+ and K+ declined quickly. Ninety-five percent of attenuated NH4+ was released by the soil. Therefore, the attenuation of NH4+ is reversible but this occurs over several pore volumes at concentrations lower than those in the simulated contaminant and therefore would not result in a mass loading to the environment. Cation exchange was identified as the mechanism responsible for the release of the adsorbed ammonium and potassium into the soil pore water.
144

On efficient recommendations for online exchange markets

Abbassi, Zeinab 11 1900 (has links)
Motivated by the popularity of marketplace applications over social net works, we study optimal recommendation algorithms for online exchange markets. Examples of such markets include peerflix. corn and readitswapit.co.uk. We model these markets as a social network in which each user has two as sociated lists: The item list, i.e, the set of items the user is willing to give away, and the wish list, i.e., the set of items the user is interested in receiv ing. A transaction involves a user giving an item to another user. Users are motivated to engage in transactions in expectation of realizing their wishes. Wishes may be realized by a pair of users swapping items corresponding to each other’s wishes, but more generally by means of users exchanging items through a cycle, where each user gives an item to the next user in a cycle, in accordance with the receiving user’s wishes. In this thesis, we first consider the problem of how to efficiently gener ate recommendations for item exchange cycles in an online market social network. We consider deterministic and probabilistic models and show that under both models, the problem of determining an optimal set of recommen dations that maximizes the expected value of items exchanged is NP-hard and develop efficient approximation algorithms for both models. Next, we study exchange markets over time and try to optimize users’ waiting times, and fairness whereby fairness we mean: give higher priority to users who contribute more to the system in addition to maximizing expected value. We show that by introducing the concept of points, average waiting time can be improved by a large factor. By designing a credit system, we try to maxi mize fairness in the system. We show not only is the fairness optimization problem NP-hard, but also inapproximable within any multiplicative factor. We propose two heuristic algorithms, one of which is based on rounding the solution to a linear programming relaxation and the other is a greedy algorithm. For both the one-shot market and the overtime market studied in this thesis, we conduct a comprehensive set of experiments, and explore the performance and also scalability of the proposed algorithms. Our experiments suggest that the performance of our algorithms in practice could be much better than the worst-case performance guarantee factors.
145

Simulated plume development and decommissioning using the breakthrough curves of five cations

Rinas, Crystal Dawn 11 July 2011 (has links)
The primary objective of this research was to investigate multicomponent transport of five major cations, Ca2+, Mg2+, NH4+, K+ and Na+, in laboratory soil columns. The soil columns were packed with soils from two different sites and were equilibrated with fresh groundwater from each respective site. Experimental data was obtained by flushing a simulated contaminant through the soil columns. The soil columns were then flushed with fresh groundwater to simulate decommissioning activities. The breakthrough data and soil exchange capacities obtained from both tests were used to identify key processes affecting the transport of the geochemical species. During the simulated contaminant flushing stage, NH4+ and K+ replaced Ca2+ and Mg2+ on the soil exchange sites. Breakthrough of NH4+ was attenuated by factors of 3.2 and 6 for Sites 1 and 2 soils, respectively. Breakthrough of K+ was attenuated by factors of 3.2 and 5.4 for Sites 1 and 2 soils, respectively. Generally, ions with higher valency will exchange for those of lower valency, but in this case the majority of the ions (NH4+ and K+) in the solution has a lower valency and will exchange with those of higher valency by mass action. Ca2+ was the first to be replaced, followed by Mg2+ once the ionic strength of the solution increased. The displacement of calcium and magnesium created a concentration pulse of these cations that coincides with the chloride breakthrough curve. Calcium and magnesium concentrations reached up to approximately 275% and 2000%, respectively, higher than the freshwater originally in the column. During the freshwater flushing stage, freshwater infiltrated the soil columns to assess the permanency of contaminant attenuation and to identify the geochemical mechanisms of contaminant release. Concentrations of NH4+ and K+ declined quickly. Ninety-five percent of attenuated NH4+ was released by the soil. Therefore, the attenuation of NH4+ is reversible but this occurs over several pore volumes at concentrations lower than those in the simulated contaminant and therefore would not result in a mass loading to the environment. Cation exchange was identified as the mechanism responsible for the release of the adsorbed ammonium and potassium into the soil pore water.
146

Anion exchange at the interfaces of mixed anion III-V heterostructures grown by molecular beam epitaxy

Brown, Terence D. 25 November 2003 (has links)
The objective of this research was to investigate the microscopic processes occurring at the interfaces of mixed anion III-V heterostructures grown by molecular beam epitaxy (MBE). In particular, efforts were made to characterize the dominant chemical and physical mechanisms that lead to anion exchange and to develop semi-empirical models capable of predicting the atomic scale structure and composition at the interfaces of mixed anion heterostructures for the As/P and Sb/As material systems. This research considers the MBE growth of 20-period superlattices (SLs) formed by allowing a dissimilar anion flux to impinge on a static group-V stabilized surface. Statistical experimental design was used to determine the effects of substrate temperature, V/III growth flux ratio, and anion exposure time on the anion exchange process. The superlattice structures were analyzed via high resolution x-ray diffraction (HRXRD) and simulation, RHEED analysis, x-ray photoelectron spectroscopy (XPS), and other techniques, which allowed for the determination of both chemical composition and atomic structure at the interfaces. Finally, a semi-empirical hybrid neural network was developed that quantifies the effects of MBE growth processes at the interfaces of mixed anion III-V heterostructures by incorporating a first principles kinetic model with back-propagation neural networks.
147

Nonlinear adjusted process of industry countries' exchange rate¡Gempirical analysis of Panel STAR model

Cheng, Wei-chun 25 June 2010 (has links)
Abstract The purpose of this paper is to research the countries' exchange rates. The paper is organized around the empirical modeling method which is devised by Van Dijk, D.; Terӓsvirta, T.; Franses, P.H.(2002) and Van Dijk, D.; Terӓsvirta, T.; González, A.(2005). It consists of estimation, specification tests, and forecast stages. The data is chosen from 1974M1 to 2008M12. We set the data from 1974M1 to 2003M12 as in-sample period, and from 2003M1 to 2008M12 as out-of-sample period. The macroeconomic variables considered in this paper include nominal exchange rates and real exchange rates. We get four important empirical results in this paper. First, the STAR model shows that every countries exists ¡§eleventh month effects¡¨. Second, the coefficient of nonlinear in Denmark¡¦s, France¡¦s, Germany¡¦s, Italy¡¦s, Spain¡¦s and UK¡¦s model are statistically significant. This result implies that the government of Japan had been intervening significantly in foreign exchange markets. And the government of other countries had been not intervening in foreign exchange markets. Third, the gamma value of the Panel model is statistically significant but slight. We can conclude that nominal exchange rates and real exchange rates exist relationship in long terms but not in short terms. Fourth, the forecast abilities of two models are almost better than random walk model.
148

Investigation of the States of Water in Proton Exchange Membrane Nafion 117 with Nuclear Magnetic Resonance Relaxation and Exchange

Wu, Zhen 10 September 2012 (has links)
The clustered water and interfacial water in Nafion 117 membrane have been quantified by NMR deuterium and proton experiments. The oscillation of intensity profile in 2H CPMG sequence with large duration time is induced by the residual quadrupolar interaction in clustered water. While the intensity profile of 2H CPMG sequence at short duration time followed the rule of exponential decay which is the consequence of the profile-overlapping between clustered water with residual quadrupolar interaction and interfacial water with susceptibility effect. The populations of clustered water and interfacial water in fully hydrated membrane are estimated by quadrupolar echo sequence. The population of former and latter is 70% and 30%,respectively. At an elevated temperature, water in cluster region can transport to the interfacial region and result in change of intensity for proton spectrum. The activation energy of translational diffusion of interfacial water is lower than that of clustered water due to the strong binding energy between sulfonate group and water molecule. The rf-heating effect on the proton spectrum of clustered water also has been explored by 1H CPMG and rotating-frame-relaxation-dispersion experiments. The dielectric response to a time-dependent external electric field provides a source of heat which causes a drift in chemical shift and interfere with transverse relaxation .
149

The Developed Patterns of China Renminbi Exchange Rate

Wu, I-chun 08 February 2006 (has links)
The main purpose of the study is to investigate the exchange rate trend of China Renminbi from 1949 to nowadays, and predict the possibilities of the developed trend of China Renminbi in the future to investigate the problems of Chins Renminbi at present. It can divide China Renminbi into three periods, there are Centrally Planned Economy Period (1949~1979), Export to Accumulate Foreign Reserve (1980~1993), and Economy Adjustment Period (1994 to nowadays). The rate standard of Renminbi is usually under the China Economy policy consideration. First of all, the China Renminbi of Centrally Planned Economy Period is based on the policy consideration of the heavy industrialization, and it tends to overvalue the rate exchange to decrease the import prime cost. This condition is similar to East Europe countries before Soviet Union dismissed. Second, the Export to Accumulate Foreign Reserve tends to decrease the export cost to solicit the business. And it tents to underestimate the rate exchange similar to Taiwan of 1970s and Japan after World War II, before Plaza Accord. Moreover, the Renminbi of Economy Adjustment Period overvalued the rate exchange, but it keeps stable. The overvalued and stable standard of rate exchange strengthens the export competition of China. At the same time, it accumulate great deal of Foreign reserve which similar to the development countries of Southeast Asian to adopt Fixed Exchange Rate Regime Pegged to US Dollar. China accumulate great deal of foreign exchange because of the overvalued rate exchange, and it made the rate standard of Renminbi concerned by international. China can not self-contained after entering WTO, they have to face the opening market and the restriction of international regulations. China restricts itself by the textile industry, and they purchase foreign bond (American bond) to decrease the pressure of the appreciation of Renminbi. Even if the rate system of Renminbi has change from control the dollar to basket-pegged exchange rate regime, and it does not break away the connection between Hong Kong currencies. The Hong Kong currencies have risk of Hot Money. China still can not open their capital during the short term time to make the Renminbi floating and become convertible currency because of their economy circumstance; however, the expected long term rate of Renminbi revaluation is a necessary trend of the future.
150

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Lin, Bing-Rong 31 July 2002 (has links)
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