Mixed population Minority Game with generalized strategies

We present a quantitative theory, based on crowd effects, for the market volatility in a Minority Game played by a mixed population. Below a critical concentration of generalized strategy players, we find that the volatility in the crowded regime remains above the random coin-toss value regardless of the "temperature" controlling strategy use. Our theory yields good agreement with numerical simulations.Comment: Revtex file + 3 figure

Observations of Cavitation on a Three-Dimensional Oscillating Hydrofoil

A test apparatus was designed and constructed to observe the effect of sinusoidal pitching oscillations on the cavitation of three-dimensional hydrofoils. The apparatus is capable of oscillating hydrofoils at a rate up to 50 Hz and provides for adjustments in oscillation amplitude and mean angle of attack. Observations of the effect of pitching oscillation on cavitation have been made for a NACA 64-309 (modified) hydrofoil operating at its designed mean angle of attack of 7 degrees with an oscillation amplitude of 2 degrees. Photographs illustrating the interaction between natural cavity shedding frequencies and the foil reduced frequency are included

A microcontroller system for investigating the catch effect: Functional electrical stimulation of the common peroneal nerve

Correction of drop foot in hemiplegic gait is achieved by electrical stimulation of the common peroneal nerve with a series of pulses at a fixed frequency. However, during normal gait, the electromyographic signals from the tibialis anterior muscle indicate that muscle force is not constant but varies during the swing phase. The application of double pulses for the correction of drop foot may enhance the gait by generating greater torque at the ankle and thereby increase the efficiency of the stimulation with reduced fatigue. A flexible controller has been designed around the Odstock Drop Foot Stimulator to deliver different profiles of pulses implementing doublets and optimum series. A peripheral interface controller (PIC) microcontroller with some external circuits has been designed and tested to accommodate six profiles. Preliminary results of the measurements from a normal subject seated in a multi-moment chair (an isometric torque measurement device) indicate that profiles containing doublets and optimum spaced pulses look favourable for clinical use

Evaluation of the Environmental Impact of Milk Quotas

The aim of this study is to examine the environmental impacts of the different systems for allocation and transfer of milk quota under the Common Agricultural Policy (CAP) in individual Member States of the European Union (EU). In particular, it seeks to identify the ways in which differences in the implementation of milk quota regimes can impact on various sectoral and farm management trends and the environmental implications of these

Limitations of adjustment for reporting tendency in observational studies of stress and self reported coronary heart disease

Recently, observational evidence has been suggested to show a causal association between various "psychosocial" exposures, including psychological stress, and heart disease. Much of this evidence derives from studies in which a self reported psychosocial exposure is related to an outcome dependent on the subjective experience of coronary heart disease (CHD) symptoms. Such outcomes may be measured using standard symptom questionnaires (like the Rose angina schedule). Alternatively they may use diagnoses of disease from medical records, which depend on an individual perceiving symptoms and reporting them to a health worker. In these situations, reporting bias may generate spurious exposure-outcome associations. For example if people who perceive and report their life as most stressful also over-report symptoms of cardiovascular disease then an artefactual association between stress and heart disease will result

Loss of redundant gene expression after polyploidization in plants

Based on chromosomal location data of genes encoding 28 biochemical systems in allohexaploid wheat,Triticum aestivum L. (genomes AABBDD), it is concluded that the proportions of systems controlled by triplicate, duplicate, and single loci are 57%, 25%, and 18% respectively

Directed Explicit Model Checking with HSF-SPIN

We present the explicit state model checker HSF-SPIN which is based on the model checker SPIN and its Promela modeling language. HSF-SPIN incorporates directed search algorithms for checking safety and a large class of LTL-specified liveness properties. We start off from the A* algorithm and define heuristics to accelerate the search into the direction of a specified failure situation. Next we propose an improved nested depth-first search algorithm that exploits the structure of Promela Never-Claims. As a result of both improvements, counterexamples will be shorter and the explored part of the state space will be smaller than with classical approaches, allowing to analyze larger state spaces. We evaluate the impact of the new heuristics and algorithms on a set of protocol models, some of which are real-world industrial protocols

Magneto-x-ray effects in transition-metal alloys

We present a theory that combines the relativistic spin-polarized version of the Koringa-Kohn-Rostoker coherent-potential approximation theory and the macroscopic theory of magneto-optical effects enabling us to calculate magneto-x-ray effects from first principles. The theory is illustrated by calculation of Faraday and Kerr rotations and ellipticities for transition-metal alloys

Generalized strategies in the Minority Game

We show analytically how the fluctuations (i.e. standard deviation) in the Minority Game (MG) can be made to decrease below the random coin-toss limit if the agents use more general behavioral strategies. This suppression of the standard deviation results from a cancellation between the actions of a crowd, in which agents act collectively and make the same decision, and an anticrowd in which agents act collectively by making the opposite decision to the crowd.Comment: Revised manuscript: a few minor typos corrected. Results unaffecte