Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vii, 83 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 53-57).

Univ., Diss., 2010--Marburg.

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Two important problems namely a versatile, efficient communication system and allocation of processors to processes are analysed. An efficient communication system has been developed, in which a central controller, the bus-master, dynamically configures the point-to-point network formed by the links of the transputers. The links are used to form a point-to-point network. An identical kernel resides on each of the nodes. This kernel is responsible for all communications on behalf of the user processes. It makes ConnectLink and ReleaseLink requests to the central controller and when the connections are made it sends the the messages through the connected link to the destination node. If direct connection to the destination node cannot be made then the message is sent to an intermediate node, the message hops through intermediate nodes until it reaches the destination node. The communication system developed provides low latency communication facility, and the system can easily be expanded to include a large number of transputers without increasing interprocess communication overhead by great extent. Another problem, namely the Module Assignment Problem (MAP) is an important issue at the time of development of distributed systems. MAPs are computationally intractable, i.e. the computational requirement grows with power of the number of tasks to be assigned. The load of a distributed system depends on both module execution times, and intermodule communication cost (IMC). If assignment is not done with due consideration, a module assignment can cause computer saturation. Therefore a good assignment should balance the processing load among the processors and generate minimum inter-processor communication (IPC) ( communication between modules not residing on the same processor). Since meeting the deadline constraint is the most important performance measure for RTDPS, meeting the response time is the most important criteria for module assignment. Understanding this we have devised a scheme which assigns processes to processors such that both response time constraints and periodicity constraints are met. If such an assignment is not possible, assignment would fail and an error would be generated. Our assignment algorithm does not take into consideration factors such as load balancing. We believe that the most important factor for RTDPS is meeting the deadline constraints and that's what our algorithm accomplishes. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

The potential real-time control (RTC) has to improve the performance of existing stormwater management systems is a topic of increasing interest as hydraulic and hydrologic modeling capabilities proliferate. The benefits of incorporating precipitation forecast data into a RTC algorithm to allow for prediction-based control of an urban watershed is explored using an EPA SWMM 5.1 watershed model. One reactive and two predictive RTC algorithms are simulated in various configurations across seven dry detention ponds located in the 162 hectare urbanized watershed. The hydraulic benefits they provide at the site and watershed outlet in regards to peak flow and the flow duration curve are compared to conventional, static control. The ponds retrofit with the novel predictive RTC algorithm had lower peak flows during 24-hour design storms more consistently than when retrofit with reactive RTC. The duration of erosive flows at the site level was decreased by the novel predictive RTC in most cases. Improvements at the watershed outlet depended on where RTC was applied as hydrograph compounding was observed during some RTC implementations. / Master of Science / The consequences of watershed urbanization on nearby waterways has become a more relevant concern as urbanization increases and climate change continues to develop. Conventional stormwater management practices are employed to control peak flows from urbanized drainage areas for certain design storm criteria. Real-time control (RTC) technology has the potential to enable existing stormwater facilities to improve their performance during storm events different from their design conditions. This study compares the performance of several reactive and predictive rule-based RTC algorithms simulated as retrofits on seven dry detention ponds in a 162 hectare urbanized watershed. The results indicate that RTC algorithms that use rainfall forecast data for predictive decision making have the most potential to reduce stream erosion when applied appropriately throughout the watershed.

In this dissertation, adaptive predictive feedback control is used to suppress plate vibrations. The adaptive predictive controller consists of an on-line identification technique coupled with a control scheme. Various system identification techniques are investigated and implemented including batch least squares, projection algorithm, and recursive least squares. The control algorithms used include Generalized Predictive Control and Deadbeat Predictive Control. This dissertation combines system identification and control to regulate broadband disturbances in modally-dense structures. As it is assumed that the system to be regulated is unknown or time varying, the control schemes presented in this work have the ability to identify and regulate a plant with only an initial estimate of the system order. In addition, theoretical development and experimental results presented in this work confirm the fact that an adaptive controller operating in the presence of disturbances will automatically incorporate an internal noise model of the disturbance perturbing the plant if the system model order is chosen sufficiently large. It is also shown that the adaptive controller has the ability to track changes in the disturbance spectrum as well as track a time varying plant under certain conditions. This work presents a broadband multi-input multi-output control scheme which utilizes both the DSP processor and the PC processor in order to handle the computational demand of broadband regulation of a modally-dense plant. Also, the system identification technique and the control algorithm may be combined to produce a direct adaptive control scheme which estimates the control parameters directly from input and output data. Experimental results for various control techniques are presented using an acoustic plant, a rectangular plate with clamped boundary conditions, and a time varying plate. / Ph. D.

<p>Server-based architectures have recently generated more interests and are currently considered for usage for communication in networks. In parallel, switched Ethernet technology has been widely adopted and used in lots of networked systems. Current requirements of networks for supporting real-time guarantees while being flexible at the same time have made the network designers to consider addition of some features to common switches. The FTT-Enabled Ethernet switch is a switch that has been developed to support the FTT (Flexible Time Triggered) paradigm. Recently, servers have been added in these types of switches in order to efficiently manage their allocated bandwidth to different types of messages.</p><p>A hierarchical network of Ethernet switches might be designed in different ways according to the overall goals and properties of the network. In this thesis, after a study on different design solutions, an architecture has been proposed based on FTT-enabled switches, motivated by their support of real-time constraints and server-based communication features. After having created the architecture, a protocol for bandwidth reservation for this hierarchically composed Ethernet switch architecture is developed. Behavior of the designed protocol is described in detail and it has been modeled using Uppaal. Moreover, the temporal behavior (timing) of the network is presented.</p>

Server-based architectures have recently generated more interests and are currently considered for usage for communication in networks. In parallel, switched Ethernet technology has been widely adopted and used in lots of networked systems. Current requirements of networks for supporting real-time guarantees while being flexible at the same time have made the network designers to consider addition of some features to common switches. The FTT-Enabled Ethernet switch is a switch that has been developed to support the FTT (Flexible Time Triggered) paradigm. Recently, servers have been added in these types of switches in order to efficiently manage their allocated bandwidth to different types of messages. A hierarchical network of Ethernet switches might be designed in different ways according to the overall goals and properties of the network. In this thesis, after a study on different design solutions, an architecture has been proposed based on FTT-enabled switches, motivated by their support of real-time constraints and server-based communication features. After having created the architecture, a protocol for bandwidth reservation for this hierarchically composed Ethernet switch architecture is developed. Behavior of the designed protocol is described in detail and it has been modeled using Uppaal. Moreover, the temporal behavior (timing) of the network is presented.

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<p>This thesis describes a further development of a building block for programmable devices in embedded systems handling real-time functionality.</p><p>Embedded systems are included in a variety of products within different technical areas such as industrial automation, consumer electronics, automotive industry, and communication-, and multimedia systems. Products ranging from trains and airplanes to microwave ovens and washing machines are controlled by embedded systems.</p><p>Programmable devices constitute a part of these embedded systems. Today, a programmable device can include a complete system containing building blocks connected with each other via programs written using a hardware description language. The programmable devices can be programmed and changed over and over again and this flexibility makes it possible to explore how these building blocks can best be designed in relation to system requirements, before final implementation.</p><p>This thesis describes a further development of a building block for programmable devices implemented in a non-traditional way, i.e., the implementation is written using both hardware description language and traditional software languages. This new building block handles real-time functionality in a non-traditional way that enables certain benefits, such as increased performance, predictability and less memory consumption. Using a non-traditional implementation also has its drawbacks, and e.g., extensions and adjustments can be hard to handle since modifications are required in both hardware and software programming languages.</p><p>The new building block was investigated in order to see how it could be facilitated when used for real-time functionality. The configurability of the block was extended which enables further customization of the building block. This leads to the possibility to use the block within a wider spectrumof applications. It is also possible to reduce the size and cost of the final product since resource usage can be optimized.</p><p>Furthermore, a mathematicalmodel estimating resource usage for real-time functionality has been developed. The model enables distinctive trade-offs comparisons, and guidance for system designers, when considering what type of real-time operating system to use in a certain design.</p>