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The production of bio-ethanol from lignocellulosic material requires a more efficient process to be feasible and compete with products from fossil fuels. There is a need to rapidly and nondestructively be able to determine key components during fermentation. Raman spectroscopy is a technique, which can be used to monitor the fermentation process in real-time and provide information about key components which can be accessed immediately, thus facilitating process control. A continuous system with membrane cell recycling was set up and fermentations were performed using Saccharomyces cerevisiae ATCC 96581. Fermentations were performed to test for optimal dilution rates and operating times, the effect of different sugar concentrations in the media feed, and which position in the system was optimal for Raman data collection. Raman data and aliquot samples for HPLC validation were continuously collected throughout the fermentations. Raman data was analysed with PLS models to obtain component concentrations, for which RMSE was calculated in order to compare to HPLC validation set. Fermentations were performed with synthetic glucose media as well as with poplar hydrolysate. It was shown that the continuous system with membrane cell recycling could achieve a glucose-to-ethanol conversion of between 75-100%. The process could be sufficiently monitored by Raman spectroscopy, and predicted concentrations were within the range of the validation set in most cases. However, the error of prediction varied between the different fermentations.

As multi-core systems are becoming more popular in real time embedded systems, strict timing requirements for accessing shared resources must be met. In particular, a detailed latency analysis for Double Data Rate Dynamic RAM (DDR DRAM) is highly desirable. Several researchers have proposed predictable memory controllers to provide guaranteed memory access latency. However, the performance of such controllers sharply decreases as DDR devices become faster and the width of memory buses is increased. Therefore, a novel and composable approach is proposed that provides improved latency bounds compared to existing works by explicitly modeling the DRAM state. In particular, this new approach scales better with increasing number of cores and memory speed. Benchmark evaluation results show up to a 45% improvement in the worst case task execution time compared to a competing predictable memory controller for a system with 16 cores.

Global illumination techniques are used to improve the realism of 3D scenes. Calculating accurate global illumination requires a method for solving the rendering equation. However, the integral form of this equation cannot be evaluated. This thesis presents research in non real-time illumination techniques which are evaluated with a finite number of light rays. This includes a new technique which improves realism of the scene over traditional techniques. All computer rendering requires distortion free texture mapping to appear plausible to the eye. Inverse texture mapping, however, can be numerically unstable and computationally expensive. Alternative techniques for texture mapping and texture coordinate generation were developed to simplify rendering. Real-time rendering is improved by pre-calculating non real-time reflections. The results of this research demonstrate that a polynomial approximation of reflected light can be more accurate than a constant approximation. The solution improves realism and makes use of new features in graphics hardware.

Turtle mobile robot which is able to interact intelligently with a dynamically changing environment.

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This thesis presents a link-level latency analysis for real-time network-on-chip interconnects that use priority-based wormhole switching. This analysis incorporates both direct and indirect interferences from other traffic flows, and it leverages pipelining and parallel transmission of data across the links. The resulting link-level analysis provides a tighter worst-case upper-bound than existing techniques, which we verify with our analysis and simulation experiments. Our experiments show that on average, link-level analysis reduces the worst-case latency by 28.8%, and improves the number of flows that are schedulable by 13.2% when compared to previous work.

Global illumination techniques are used to improve the realism of 3D scenes. Calculating accurate global illumination requires a method for solving the rendering equation. However, the integral form of this equation cannot be evaluated. This thesis presents research in non real-time illumination techniques which are evaluated with a finite number of light rays. This includes a new technique which improves realism of the scene over traditional techniques. All computer rendering requires distortion free texture mapping to appear plausible to the eye. Inverse texture mapping, however, can be numerically unstable and computationally expensive. Alternative techniques for texture mapping and texture coordinate generation were developed to simplify rendering. Real-time rendering is improved by pre-calculating non real-time reflections. The results of this research demonstrate that a polynomial approximation of reflected light can be more accurate than a constant approximation. The solution improves realism and makes use of new features in graphics hardware.

Due to advances in capacity, speed, and economics, NAND-based flash memory technology is increasingly integrated into all types of computing systems, ranging from enterprise servers to embedded devices. However, due to its unpredictable up-date behavior and time consuming garbage collection mechanism, NAND-based flash memory is difficult to integrate into hard-real-time embedded systems. In this thesis, I propose a performance model for flash memory garbage collection that can be used in conjunction with a number of different garbage collection strategies. I describe how to model the cost of reactive (lazy) garbage collection and compare it to that of more proactive schemes. I develop formulas to assess the schedulability of hard real- time periodic task sets under simplified memory consumption models. Results show that I prove the proactive schemes achieve the larger maximum schedulable utilization than the traditional garbage collection mechanism for hard real-time systems in flash memory.

This thesis explores how granular synthesis can be used in live performances. The early explorations of granular synthesis are first investigated, leading up to modern trends of electronic performance involving granular synthesis. Using this background it sets about to create a granular synthesis instrument that can be used for live performances in a range of different settings, from a computer quartet, to a flute duet. The instrument, an electronic fish called the poseidon, is documented from the creation and preparation stages right through to performance.