Analysis and Optimisation of Hierarchically Scheduled Multiprocessor Embedded Systems

We present an approach to the analysis and optimisation of heterogeneous multiprocessor embedded systems. The systems are heterogeneous not only in terms of hardware components, but also in terms of communication protocols and scheduling policies. When several scheduling policies share a resource, they are organised in a hierarchy. In this paper, we first develop a holistic scheduling and schedulability analysis that determines the timing properties of a hierarchically scheduled system. Second, we address design problems that are characteristic to such hierarchically scheduled systems: assignment of scheduling policies to tasks, mapping of tasks to hardware components, and the scheduling of the activities. We also present several algorithms for solving these problems. Our heuristics are able to find schedulable implementations under limited resources, achieving an efficient utilisation of the system. The developed algorithms are evaluated using extensive experiments and a real-life example.     

Random Doping Fluctuations of Small-Signal Parameters in Nanoscale Semiconductor Devices

Random dopant induced fluctuations of small-signal parameters in nanoscale semiconductor devices are analyzed by using the perturbation (linearization) technique. This technique requires only first-order derivatives of the transport equations, which makes it suitable for implementation in commercial device simulators. Sample numerical results are presented for a 25 nm channel length n-channel MOSFET device.     

Power quality impact of a sea located hybrid wind park

The power quality impact of a 2.5 MW wind park has been measured and analyzed. The turbines in the park operate at variable speed at low wind speeds and at fixed speed at higher wind speeds. The harmonic current injection is low and the calculated flicker contribution is seldom above 0.25. The wind park also has the potential to maintain the voltage on the supplying grid below a certain limit, in this case 11 kV     

Dynamic elastic properties of hardened experimental mortar bars affected by accelerated alkali–silica reactivity test: a laboratory approach

Bulletin of Engineering Geology and the Environment - The evaluation of ASR sensitivity of aggregates is of utmost importance due to durability and safety of structures and also due to economic...     

Analytical estimation of breakdown voltage in insulated-gate bipolar transistors

Journal of Computational Electronics - In this paper, we derive closed-form equations for the breakdown voltage of punch-through and non-punch-through insulated-gate bipolar transistors (IGBTs)....     

A hybrid ceramic-polymer composite fabricated by co-curing lay-up process for a strong bonding and enhanced transient thermal protection

A hybrid ceramic-polymer composite is fabricated by a co-curing lay-up process by combining a carbon nanotube (CNT) reinforced ceramic composite thin film with a carbon fiber reinforced polymer (CFRP) composite substrate. The ceramic nanocomposite thin film has good flexibility, thermal conductivity and high temperature tolerance. The polymer composite substrate is a carbon fiber reinforced bismaleimide composite that is widely used in aerospace and automotive industries. Finite element analysis (FEA) is used to investigate the maximum survival temperature with different thicknesses of the ceramic nanocomposite. The resultant hybrid composite shows good structural integrity and displays a pull-off bonding strength up to 8.3?MPa. In addition, thermal study illustrates that such a flexible CNT reinforced ceramic composite can effectively protect CFRP in an elevated temperature environment by delaying transient thermal conduction.     

High-throughput automated dissolution method applicable for a wide dose range of controlled release pellets

The aim of the present study was to demonstrate the application of an automated high-throughput (HT) dissolution method as a useful screening tool for characterization of controlled release pellets in the formulation development phase. Five controlled release pellet formulations with drug substances exhibiting high or low solubility were chosen to investigate the correlation of the automated HT dissolution method with the conventional dissolution testing. Overall, excellent correlations (R^2?>^?0.96) between the HT and the conventional dissolution method were obtained. In one case the initial unsatisfactory correlation (R^2?=^?0.84) and poor method agreement (SD?=?12.5) was improved by optimizing the HT dissolution method with design of experiment approach. Here in comparison to initial experimental HT dissolution settings, increased amount of pellets (25% of the capsule filling mass), lower temperature (22?°C) and no shaking resulted in significantly better correlation (R^2?=^?0.97) and method agreement (SD?=?5.3). These results show that such optimization is valuable for the development of HT dissolution methods. In conclusion, the high correlation of dissolution profiles obtained from the conventional and the automated HT dissolution method combined with low within-sample and measurement system variability, justifies the utilization of the automated HT dissolution method during development phase of controlled release pellets.     

Heat treatment influence on the structural properties of supported Ni nanoclusters

Ni nanoclusters supported on Al₂O₃ were prepared using a coprecipitation method. A heat treatment at different temperatures was applied. The obtained samples were analyzed by X-ray diffraction (XRD), X-ray absorption spectroscopy and X-ray photoelectron spectroscopy in order to determine their global, local and electronic structures. The average particle size, the mean squares of the microstrain, the particle size and microstrain distribution functions of the supported Ni nanoclusters were determined by the XRD method using a generalized Fermi function for the approximation of the X-ray line. The recrystallization induced during the heat treatment process was analyzed. The present study indicated strong deformation of the local structure of the active metal in all of the samples investigated due to the metal-support interaction and the effects of the small particle size. Electronic structural investigations showed the presence of Ni in a metallic state as well as Ni²⁺ on the cluster surfaces.