746 research outputs found
Abstract State Machines 1988-1998: Commented ASM Bibliography
An annotated bibliography of papers which deal with or use Abstract State
Machines (ASMs), as of January 1998.Comment: Also maintained as a BibTeX file at http://www.eecs.umich.edu/gasm
Planning and Resource Management in an Intelligent Automated Power Management System
Power system management is a process of guiding a power system towards the objective of continuous supply of electrical power to a set of loads. Spacecraft power system management requires planning and scheduling, since electrical power is a scarce resource in space. The automation of power system management for future spacecraft has been recognized as an important R&D goal. Several automation technologies have emerged including the use of expert systems for automating human problem solving capabilities such as rule based expert system for fault diagnosis and load scheduling. It is questionable whether current generation expert system technology is applicable for power system management in space. The objective of the ADEPTS (ADvanced Electrical Power management Techniques for Space systems) is to study new techniques for power management automation. These techniques involve integrating current expert system technology with that of parallel and distributed computing, as well as a distributed, object-oriented approach to software design. The focus of the current study is the integration of new procedures for automatically planning and scheduling loads with procedures for performing fault diagnosis and control. The objective is the concurrent execution of both sets of tasks on separate transputer processors, thus adding parallelism to the overall management process
Effective interprocess communication (IPC) in a real-time transputer network
The thesis describes the design and implementation of an interprocess communication (IPC)
mechanism within a real-time distributed operating system kernel (RT-DOS) which is
designed for a transputer-based network. The requirements of real-time operating systems
are examined and existing design and implementation strategies are described. Particular
attention is paid to one of the object-oriented techniques although it is concluded that these
techniques are not feasible for the chosen implementation platform. Studies of a number of
existing operating systems are reported. The choices for various aspects of operating system
design and their influence on the IPC mechanism to be used are elucidated. The actual design
choices are related to the real-time requirements and the implementation that has been
adopted is described. [Continues.
Network control for a multi-user transputer-based system.
A dissertation submitted to the Faculty of Engineering, University of the
Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of
Master of Science in EngineeringThe MC2/64 system is a configureable multi-user transputer- based system which was
designed using a modular approach. The MC2/64 consists of MC2 Clusters which are
connected using a modified Clos network. The MC2 Clusters were designed and
realised as completely configurable modules using and extending an algorithm based on
Eulerian cycles through a requested graph. This dissertation discusses the configuration
algorithm and the extensions made to the algorithm for the MC2 Clusters.
The total MC2/64 system is not completely configurable as a MC2 Cluster releases only
a limited number of links for inter-cluster connections. This dissertation analyses the
configurability of MC2/64, but also presents algorithms which enhance the usability of
the system from the user's point of view.
The design and the implementation of the network control software are also submitted
as topics in this dissertation. The network control software must allow multiple users to
use the system, but without them influencing each other's transputer domains.
This dissertation therefore seeks to give an overview of network control problems and
the solutions implemented in current MC2/64 systems. The results of the research
done for this dissertation will hopefully aid in the design of future MC2 systems which
will provide South Africa with much needed, low cost, high performance computing
power.Andrew Chakane 201
Enable++ : a second generation FPGA processor
In the computing community field programmable processors are going to fill the niche for special purpose computing devices. A typical example is ultra-fast pattern recognition in experimental particle physics - a task for which we constructed two years ago Enable- 1, an FPGA processor rather specialized for pattern recognition algorithms in μs domain, but also provided with modest features for coping with more general applications. This paper presents the follow-up modell Enable++, a 2nd generation FPGA processor that offers several substantial enhancements over the previous system for a wider range of applications: Enable++ is structured into three different state-of-the-art modules for providing computing power, flexible and high-speed I/O communication and powerful intermodule communication with a raw bandwidth of 3.2 GByte/s by an active backplane. The technical realization of all three modules is guided by the maximum usage of field programmable logic. The actual demand of computing-and I/O-power can be satisified by the number of modules plugged into the crate. Enhanced features of Enable++ comprise the configurable processor topology provided by programmable crossbar switches. In combination with the 4 x 4 FPGA array and 12 MByte distributed RAM the Enable++ computing core offers a strongly increased and scalable computing power. For building new applications the system offers a comfortable programming and debugging environment consisting of a compiler for the C-like hardware description language spC, a simulator and a source level debugger for hardware design. The goal in planning the hardware design environment for Enable++ from scratch is to transfer established methodologies in software design to the design of digital logic. Concerning pattern recognition tasks, we estimate that Enable++ surpasses modern RISC processors by a factor of 100 to 1000
Performance-based control system design automation via evolutionary computing
This paper develops an evolutionary algorithm (EA) based methodology for computer-aided control system design (CACSD)
automation in both the time and frequency domains under performance satisfactions. The approach is automated by efficient
evolution from plant step response data, bypassing the system identification or linearization stage as required by conventional
designs. Intelligently guided by the evolutionary optimization, control engineers are able to obtain a near-optimal ‘‘off-thecomputer’’
controller by feeding the developed CACSD system with plant I/O data and customer specifications without the need of
a differentiable performance index. A speedup of near-linear pipelineability is also observed for the EA parallelism implemented on
a network of transputers of Parsytec SuperCluster. Validation results against linear and nonlinear physical plants are convincing,
with good closed-loop performance and robustness in the presence of practical constraints and perturbations
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