Programming MPSoC platforms: Road works ahead

This paper summarizes a special session on multicore/multi-processor system-on-chip (MPSoC) programming challenges. The current trend towards MPSoC platforms in most computing domains does not only mean a radical change in computer architecture. Even more important from a SW developer´s viewpoint, at the same time the classical sequential von Neumann programming model needs to be overcome. Efficient utilization of the MPSoC HW resources demands for radically new models and corresponding SW development tools, capable of exploiting the available parallelism and guaranteeing bug-free parallel SW. While several standards are established in the high-performance computing domain (e.g. OpenMP), it is clear that more innovations are required for successful\ud deployment of heterogeneous embedded MPSoC. On the other hand, at least for coming years, the freedom for disruptive programming technologies is limited by the huge amount of certified sequential code that demands for a more pragmatic, gradual tool and code replacement strategy

An LTE Uplink Receiver PHY Benchmark and Subframe-Based Power Management

With the proliferation of mobile phones and other mobile internet appliances, the application area of baseband processing continues to grow in importance. Much academic research addresses the underlying mathematics, but little has been published on the design of systems to execute baseband workloads. Most systems research is conducted within companies who go to great lengths to protect their intellectual property. We present an open-source LTE Uplink Receiver PHY benchmark with a realistic representation of the baseband processing of an LTE base station, and we demonstrate its usefulness in investigating resource management strategies to conserve power on a TILEPro64. By estimating the workload of each subframe and using these estimates to control power-gating, we reduce power consumption by more than 24% (11% on average) compared to executing the benchmark with no estimation-guided resource management. By making available a benchmark containing no proprietary algorithms, we enable a broader community to conduct research both in baseband processing and on the systems that are used to execute such workloads

Power-Aware Resource Scheduling in Base Stations

Baseband stations for Long Term Evolution (LTE) communication processing tend to rely on over-provisioned resources to ensure that peak demands can be met. These systems must meet user Quality of Service expectations, but during non-peak workloads, for instance, many of the cores could be placed in low-power modes. One key property of such application-specific systems is that they execute frequent, short-lived tasks. Sophisticated resource management and task scheduling approaches suffer intolerable overhead costs in terms of time and expense, and thus lighter-weight and more efficient strategies are essential to both saving power and meeting performance expectations. To this end, we develop a flexible, non-propietary LTE workload model to drive our resource management studies. Here we describe our experimental infrastructure and present early results that underscore the promise of our approach along with its implications on future hardware/software codesign

Photocatalytic activity of TiO2/SWCNT and TiO2/MWCNT nanocomposites with different carbon nanotube content

With different mass ratios, titanium dioxide/carbon nanotube (0.1-10 wt% CNTcontent) nanocomposites were prepared with the aid of ultrasonication method. The structures of the various TiO2/CNT nanocomposites were characterized by electron microscopy (scanning electron microscopy, transmission electron microscopy). Their photocatalytic activity was tested by the degradation of phenol in aqueous solution under near-UV irradiation. In parallel experiments, both (SW and MW) CNT samples were treated in a reflux system with nitric acid to functionalize the nanotubes, subsequently preparing the nanocomposites in the same method. At higher CNT concentration (5, 10 wt%) the nanocomposites exhibited lower photocatalytic activity compared to the samples with lower CNT concentration, probably because the higher CNT concentration reduces the light intensity on the surfaces of TiO2 particles. Our aim was to find the best synthesis method and the optimal composition of the TiO2/CNT nanocomposites for the degradation of phenol under UV irradiation. The highest degradation rate was achieved with Aldrich anatase/functionalized single wall carbon nanotube nanocomposite (AA+f-SW1 wt%). The photocatalytic activity of this sample was significantly higher compared to the bare Aldrich anatase and Aeroxide P25 titanium dioxide reference samples which were the best photocatalysts among the investigated bare titanias. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei