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The COVAD toolbox is a MATLAB/Simulink based tool conceived and developed for the rapid analysis and simulation of stochastically driven dynamic systems. In addition to a generic Monte Carlo capability, the toolbox is also supported by traditional analytical techniques such as the adjoint and covariance analysis methods. However, these latter techniques only apply to linear systems. The objective of this paper is to explore the feasibility of extending COVAD to enhance its non-Monte Carlo capability for the analysis of non-linear systems. The present investigation will focus on the use and implementation of a well-known linearization technique known as the statistical linearization method. This technique has been used in the past in conjunction with the standard adjoint and covariance analysis method to provide sufficiently accurate solutions to certain classes of non-linear problems. Calculating the miss distance statistics of the homing loop of a generic guided missile under acceleration limiting will then be used as an example to demonstrate the utility of the software. Copyright © 2009 by the American Institute of Aeronautics and Astronautics, Inc.

The product quality of energetic materials is predominantly determined by the crystallization process applied to produce these materials. It has been demonstrated in the past that the higher the product quality of the solid energetic ingredients, the less sensitive a plastic bonded explosive containing these energetic materials becomes. The application of submicron or nanometric energetic materials is generally considered to further decrease the sensitiveness of explosives. In order to assess the product quality of energetic materials, a range of analytical techniques is available. Recent attempts within the Reduced-sensitivity RDX Round Robin (R4) have provided the EM community a better insight into these analytical techniques and in some cases a correlation between product quality and shock initiation of plastic bonded explosives containing (RS-)RDX was identified, which would provide a possibility to discriminate between conventional and reduced sensitivity grades. In this paper experimental results of two relatively new crystallization techniques are shown. Submicron and nanometric RDX particles have been produced and characterized. Also results on the characterization of different commercial RDX grades will be shown, including data related to a part of the samples received within the R4 programme. Finally, experimental data will be presented and discussed on insensitive plastic bonded explosives (PBXs). © 2008 WILEY-VCH Verlag GmbH & Co. KGaA.

The modified European Food Law (General Food Law) has been emphasizing on the need to increase consumer confidence through implementation of regulatory measures focused on increased traceability in food chain. The implementation of effective traceability systems can provide the basis of communication between actors in the production chain, and facilitate effective product recall when a food safety incident occurs. various approaches have been developed that have the potential to improve traceability of foods and food ingredients through different food chains. Electronic Data Interchange (EDI) can be a reliable way whereby traceability data can be communicated through different paths, through computer-to-computer or mobile phone networks, Internet, or private networks. Analytical techniques, based on molecular biology or isotope technology, can also be considered for the food quality issues or establishing food authenticity.

A new microfluidic approach for charge-based particle separation using combined hydrodynamic and electrokinetic effects is presented. A recirculating flow pattern is employed, generated through application of bi-directional flow in a narrow glass microchannel incorporating diverging or converging segments at both ends. The bi-directional flow in turn is a result of opposing pressure-driven flow and electro-osmotic flow in the device. Trapping and preconcentration of charged particles is observed in the recirculating flow, under conditions where the average net velocity of the particles themselves approaches zero. This phenomenon is termed flow-induced electrokinetic trapping (FIET). Importantly, the electrophoretic mobility (zeta potential) of the particles determines the flow conditions required for trapping. In this paper, we exploit FIET for the first time to perform particle separations. Using a non-uniform channel, one type of particle can be trapped according to its zeta-potential, while particles with higher or lower zeta-potentials are flushed away with the pressure-driven or electro-osmotic components, respectively, of the flow. This was demonstrated using simple mixtures of two polystyrene bead types having approximately the same size (3 m) but different zeta potentials (differences were in the order of 25 to 40 mV). To gain more insight into the separation mechanism, particle separations in straight, 3 cm-long microchannels with uniform cross-section were also studied under conditions of bi-directional flow without trapping. A thorough theoretical analysis confirmed that trapping occurs when electrokinetic and pressure-driven particle velocities are equal and opposite throughout the diverging segment. This makes it possible to predict the pressure and electric field conditions required to separate particles having defined zeta potentials. © 2009 The Royal Society of Chemistry.