Gary Johnston

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1. I n t r o d u c t i o n This paper describes the design for an operating system family called Choices being built for the Embedded Operating System (EOS) project at the University of Illinois at Urbana-Champaign. Choices embodies the notion of customized operating systems that are tailored for particular hardware configurations or for particular(More)
This paper presents three principles for the design and construction of object-oriented operating systems. These principles are based on the design of Choices, an object-oriented operating system that is implemented on the Encore Multimax shared memory multiprocessor. Choices is written entirely in C++, an object-oriented language that supports inheritance(More)
The programming of the interrupt handling mechanisms, process switching primitives, scheduling mechanisms, and synchronization primitives of an operating system for a multiprocessor require both efficient code in order to support the needs of high-performance or real-time applications and careful organization to facilitate maintenance. Although many(More)
The Choices family of operating systems exploits class hierarchies and object-oriented programming to facilitate the construction of customized operating systems for shared memory and networked multiprocessors. The software is being used in the Tapestry' laboratory to study the performance of algorithms, mechanisms, and policies for parallel systems. This(More)
All atomic force microscope (AFM) images suffer from distortions, which are principally produced by the interaction between the measured sample and the AFM tip. If the three-dimensional shape of the tip is known, the distorted image can be processed and the original surface form ‘restored’, typically by deconvolution approaches. This restored(More)
An investigation into orientation preferences shown by actin fibres within ex-situ actin as imaged by Atomic Force Microscopy (AFM) is described. Actin is a primary cytoskeletal component and is believed to play a vital role in cell structure. Actin structure images measured by AFM were analysed using automated pre-processing steps. These steps were(More)
SUMMARY Global Navigation Satellite Systems (GNSSs) involve satellites, ground stations and user equipment, and are now used to support many activities within modern societies. Among them, precise positioning for geodetic, surveying and critical real-time machine guidance applications requires a substantial investment in ground infrastructure in the form of(More)
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