AdS/QHE: Towards a Holographic Description of Quantum Hall Experiments

Transitions among quantum Hall plateaux share a suite of remarkable experimental features, such as semi-circle laws and duality relations, whose accuracy and robustness are difficult to explain directly in terms of the detailed dynamics of the microscopic electrons. They would naturally follow if the low-energy transport properties were governed by an emergent discrete duality group relating the different plateaux, but no explicit examples of interacting systems having such a group are known. Recent progress using the AdS/CFT correspondence has identified examples with similar duality groups, but without the DC ohmic conductivity characteristic of quantum Hall experiments. We use this to propose a simple holographic model for low-energy quantum Hall systems, with a nonzero DC conductivity that automatically exhibits all of the observed consequences of duality, including the existence of the plateaux and the semi-circle transitions between them. The model can be regarded as a strongly coupled analog of the old `composite boson' picture of quantum Hall systems. Non-universal features of the model can be used to test whether it describes actual materials, and we comment on some of these in our proposed model.Comment: LaTex 52 pages 11 figures. Repost improves the discussion of the probe approximation; corrects minor errors; adds references. Second repost generalizes charged solution and improves scaling discussio

Short- & Long-Run Effects of Seafood Imports on Domestic Price

Agribusiness, Community/Rural/Urban Development, Demand and Price Analysis, International Relations/Trade,

The Impact of Microeconomic Structure Adjustment and Macroeconomic Variables under NAFTA on U.S. Agriculture

Agribusiness, International Relations/Trade,

Pilot and control system modelling for handling qualities analysis of large transport aircraft

The notion of airplane stability and control being a balancing act between stability and control has been around as long as aeronautics. The Wright brothers’ first successful flights were born of the debate, and were successful at least in part because they spent considerable time teaching themselves how to control their otherwise unstable airplane. This thesis covers four aspects of handling for large transport aircraft: large size and the accompanying low frequency dynamics, the way in which lifting surfaces and control system elements are modelled in flight dynamics analyses, the cockpit feel characteristics and details of how pilots interact with them, and the dynamic instability associated with Pilot Induced Oscillations. The dynamics associated with large transport aircraft are reviewed from the perspective of pilot-in-the-loop handling qualities, including the effects of relaxing static stability in pursuit of performance. Areas in which current design requirements are incomplete are highlighted. Issues with modelling of dynamic elements which are between the pilot’s fingers and the airplane response are illuminated and recommendations are made. Cockpit feel characteristics are examined in detail, in particular, the nonlinear elements of friction and breakout forces. Three piloted simulation experiments are described and the results reviewed. Each was very different in nature, and all were designed to evaluate linear and nonlinear elements of the cockpit feel characteristics from the pilot’s point of view. These included understanding the pilot’s ability to precisely control the manipulator itself, the pilot’s ability to command the flight path, and neuro-muscular modelling to gain a deeper understanding of the range of characteristics pilots can adapt to and why. Based on the data collected and analyzed, conclusions are drawn and recommendations are made. Finally, a novel and unique PIO prediction criterion is developed, which is based on control-theoretic constructs. This criterion identifies unique signatures in the dynamic response of the airplane to predict the onset of instability

IMPLICIT PRICE AND DEMAND IN OLIGOPOLISTIC COMPETITION: AN APPLICATION TO THE U.S. TROUT MARKET

This study provides an example of how implicit price and demand models can be developed and used for empirical analysis. In particular, empirical application of these models can quantify the impact of implicit economic variables representing preference, relative price, production efficiency, the degree of price sensitivity to quantity supplied, and substitutability on market price and demand for domestic and imported products. Furthermore, the simultaneous impact of these implicit economic variables on market price and demand can be quantified using these implicit price and demand models.International Relations/Trade,

STRUCTURAL APPROACH TO ANALYZE THE EFFECTS OF EXHCHANGE RATE ON IMPORT DEMAND

The purpose of this study is to determine the impact the exchange rate has on local prices and import demand.Exchange rate, Direct and indirect effects, Korean beef market, International Relations/Trade, F10, F11, F13,

NORTH KOREAN FOOD SUPPLY AND DEMAND: AN ECONOMETRIC ANALYSIS

This study simulates North Korean food supply and demand using an econometric regression based upon neo-classical economic theory. In doing so, this study at first describes the autarky condition that exists in the closed economy of North Korea and the relationship between pro-military oriented economic policy and deficiency in the dietary needs required by the average North Korean. This study then quantifies the impact agricultural resources and policy have had on the production of food for the sample period of 1995 to 2008. Results show that food production decreases along with a decrease in agricultural input factors and with the implementation of a more pro-military oriented economic policy. Finally, this study simulates ex ante food balance. In order to meet food demand, the rate at which agricultural input factors are made available should be much more greater than the increasing rate of population, regardless of whether pro-market oriented economic policy reforms are implemented or not. And if a more pro-market approach is implemented by North Korea, the food balance appears to recover more quickly from food deficiency to food surplus given a specific level of agricultural resources.Political Economy,

Determining the Impact of Crawfish Imports on U.S. Domestic Prices

The study identifies the linkage between imports and the domestic price of crawfish. The results show a simultaneous increase in imports and domestic prices of crawfish while showing a negative relationship between domestic landings and price. Each model shows that there is a seasonality effect on the domestic price of crawfish. The study also shows that increases in the domestic supplies of shrimp, tilapia, and clams generated increases in the domestic crawfish price while increases in imported and domestic supplies of beef and imported supplies of pork decreased the domestic crawfish price.Demand and Price Analysis, International Relations/Trade,

IMPORT DEMAND SYSTEM ANALYSIS OF THE SOUTH KOREAN WINE MARKET WITH THE SOURCE DIFFERENTATED AIDS MODEL

Under the assumption of block substitutability and partial aggregation, a source differentiated AIDS model was used to estimate South Korean wine import demand. Empirical results indicate that South Korean wine consumers have a strong preference for high quality French wines. French wines are shown to be substitutes for wines from other countries in the South Korean wine market. Since the implementation of a free trade agreement between South Korea and Chile, Chilean wines have steadily increased their market share exhibiting strong price competitiveness in the South Korean wine market.wine, AIDS, block substitutability, import demand, Demand and Price Analysis,

A Demand System Analysis of the U.S. Trout Market

The objective of this study is to analyze how imported trout affects the domestic U.S. trout industry.Trout, Demand System, Import, International Relations/Trade, F10, F11, F13,