The benefits of combining seasonal anomalies and technical trading rules

Although many seasonal anomalies and technical trading rules have been shown to have predictive ability, investigations have focused only on them operating individually. We study the benefits of trading based on combinations of three of the best known effects: the moving average rule, the turn of the month effect, and the Halloween effect. We show that the rules can be combined effectively, giving significant levels of returns predictability with low risk and offering the possibility of profitable trading. This new investment approach is especially beneficial for a typical individual investor, who faces high transaction costs and is poorly diversified

Process of designing robust, dependable, safe and secure software for medical devices: Point of care testing device as a case study

This article has been made available through the Brunel Open Access Publishing Fund.Copyright © 2013 Sivanesan Tulasidas et al. This paper presents a holistic methodology for the design of medical device software, which encompasses of a new way of eliciting requirements, system design process, security design guideline, cloud architecture design, combinatorial testing process and agile project management. The paper uses point of care diagnostics as a case study where the software and hardware must be robust, reliable to provide accurate diagnosis of diseases. As software and software intensive systems are becoming increasingly complex, the impact of failures can lead to significant property damage, or damage to the environment. Within the medical diagnostic device software domain such failures can result in misdiagnosis leading to clinical complications and in some cases death. Software faults can arise due to the interaction among the software, the hardware, third party software and the operating environment. Unanticipated environmental changes and latent coding errors lead to operation faults despite of the fact that usually a significant effort has been expended in the design, verification and validation of the software system. It is becoming increasingly more apparent that one needs to adopt different approaches, which will guarantee that a complex software system meets all safety, security, and reliability requirements, in addition to complying with standards such as IEC 62304. There are many initiatives taken to develop safety and security critical systems, at different development phases and in different contexts, ranging from infrastructure design to device design. Different approaches are implemented to design error free software for safety critical systems. By adopting the strategies and processes presented in this paper one can overcome the challenges in developing error free software for medical devices (or safety critical systems).Brunel Open Access Publishing Fund

The Avalanche Mechanism for Atom Loss near an Atom-Dimer Efimov Resonance

An Efimov trimer near the atom-dimer threshold can increase the atom loss rate in ultracold trapped atoms through the {\it avalanche mechanism} proposed by Zaccanti et al. A 3-body recombination event creates an energetic atom and dimer, whose subsequent elastic collisions produce additional atoms with sufficient energy to escape from the trapping potential. We use Monte Carlo methods to calculate the average number of atoms lost and the average heat generated by recombination events in both a Bose-Einstein condensate and a thermal gas. We take into account the energy-dependence of the cross sections and the spatial structure of the atom cloud. We confirm that the number of atoms lost can be much larger than the naive value 3 if there is an Efimov trimer near the atom-dimer threshold. This does not produce a narrow loss feature, but it can significantly affect the determination of Efimov parameters.Comment: 5 pages, 3 figure

Study of zero-gravity, vapor/liquid separators

Heat exchange, mechanical separation, surface tension, and dielectrophoretic methods of separating vapor from liquid at zero gravity for vapor ventin

Stochastic geometry and topology of non-Gaussian fields

Gaussian random fields pervade all areas of science. However, it is often the departures from Gaussianity that carry the crucial signature of the nonlinear mechanisms at the heart of diverse phenomena, ranging from structure formation in condensed matter and cosmology to biomedical imaging. The standard test of non-Gaussianity is to measure higher order correlation functions. In the present work, we take a different route. We show how geometric and topological properties of Gaussian fields, such as the statistics of extrema, are modified by the presence of a non-Gaussian perturbation. The resulting discrepancies give an independent way to detect and quantify non-Gaussianities. In our treatment, we consider both local and nonlocal mechanisms that generate non-Gaussian fields, both statically and dynamically through nonlinear diffusion.Comment: 8 pages, 4 figure

Slowing heavy, ground-state molecules using an alternating gradient decelerator

Cold supersonic beams of molecules can be slowed down using a switched sequence of electrostatic field gradients. The energy to be removed is proportional to the mass of the molecules. Here we report deceleration of YbF, which is 7 times heavier than any molecule previously decelerated. We use an alternating gradient structure to decelerate and focus the molecules in their ground state. We show that the decelerator exhibits the axial and transverse stability required to bring these molecules to rest. Our work significantly extends the range of molecules amenable to this powerful method of cooling and trapping.Comment: 4 pages, 5 figure

The Unpredictability of the Most Energetic Solar Events

Observations over the past two solar cycles show a highly irregular pattern of occurrence for major solar flares, gamma-ray events, and solar energetic particle (SEP) fluences. Such phenomena do not appear to follow the direct indices of solar magnetic activity, such as the sunspot number. I show that this results from the non-Poisson occurrence for the most energetic events. This Letter also points out a particularly striking example of this irregularity in a comparison between the declining phases of the recent two solar cycles (1993-1995 and 2004-2006, respectively) and traces it through the radiated energies of the flares, the associated SEP fluences, and the sunspot areas. These factors suggest that processes in the solar interior involved with the supply of magnetic flux up to the surface of the Sun have strong correlations in space and time, leading to a complex occurrence pattern that is presently unpredictable on timescales longer than active region lifetimes (weeks) and not correlated well with the solar cycle itself.Comment: 4 page