Distributed adaptive computing systems (ACS) allow developers to design applications using multiple programmable devices. The ACS API, an API created for distributed adaptive com-puting, gives developers the ability to design scalable ACS systems in a cluster networking environment for large applications. One such application, found in the field of bioinformatics, is the DNA sequence alignment problem. This thesis presents a runtime reconfigurable FPGA implementation of the Smith-Waterman similarity comparison algorithm. Additionally, this thesis presents tools designed for the ACS API that assist developers creating applications in a heterogeneous distributed adaptive computing environment. / Master of Science

Thesis (MEng)-- Stellenbosch University, 2014. / ENGLISH ABSTRACT: The South African industry has an increasing need for manufacturing automation. However, the classical form of automation is not cost effective for the low volumes and high variance of products that are produced there. The industry may use the reconfigurable manufacturing system (RMS) concept to improve production of its products. However, industry has been unwilling to adopt the reconfigurable manufacturing systems developed in recent research projects. Due to industry’s hesitance to adopt the control platforms on which reconfigurable manufacturing systems are currently based, the focus of the thesis is on creating a reconfigurable control system using industry accepted technologies. This research focused on evaluating a Beckhoff embedded PC’s suitability as a station controller that controls a reconfigurable subsystem in an RMS. The control system for the station controller was developed using only the IEC 61131-3 programming languages and the Beckhoff programming software. This control system was evaluated by using it to control a station that is responsible for testing a circuit breaker’s tripping current and time. The developed control system was based on the ADACOR architecture because of its optimisation capabilities that were necessary to keep the cycle time of the station as low as possible. The design and implementation of the physical configuration and control system of the station is described in this thesis. The station was designed to meet the requirements of both an RMS and the case study. Because of the limitations of the IEC 61131-3 programming languages, dynamic instantiation of holons is not possible and a method was developed to simulate dynamic task holons. By making use of the embedded PC’s ability to run multiple PLCs at the same time, each type of holon was run in its own PLC thread. The developed control system and station was evaluated by conducting experiments using a laboratory test setup. The evaluation of the developed control system in this thesis proved that an RMS can be created, in the context of station control, using IEC 61131-3 and industry accepted technologies, if a hardware platform is used that allows multiple PLCs to be run in individual threads. The control approach that was created in this thesis can be used to create station control systems that offers optimised cycle times, the benefits of an RMS and the benefits of industry accepted technology. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse bedryf het 'n toenemende behoefte aan geoutomatiseerde vervaardiging. Die klassieke vorm van outomatisasie is egter nie koste effektief vir die lae volumes en hoë variansie van produkte wat in Suid Afrika geproduseer word nie. Die bedryf kan moontlik die konsep van 'n herkonfigureerbare vervaardigingstelsel (HVS) gebruik om vervaardiging te outomatiseer. Die bedryf is egter nie bereid om die herkonfigureerbare vervaardigingstelsels wat in onlangse navorsingsprojekte ontwikkel is, te aanvaar nie. As gevolg van die bedryf se huiwering om die beheerplatforms waarop herkonfigureerbare vervaardigingstelsels tans gebaseer word, te aanvaar, is die fokus van die tesis om industrie-aanvaarde tegnologie te gebruik om ‘n herkonfigureerbare beheerstelsel te skep. Hierdie navorsing fokus op die evaluering van 'n “Beckhoff embedded PC” se geskiktheid as 'n stasiebeheerder van 'n herkonfigureerbare substelsel in 'n HVS. Die beheerstelsel vir die stasie beheerder is ontwikkel deur slegs van die IEC 61131-3 programmeringstale en die Beckhoff programmering-sagteware gebruik te maak. Hierdie beheerstelsel is geëvalueer deur dit op die beheer van 'n stasie wat verantwoordelik is vir die toets stroombrekers, toe te pas. Die beheerstelsel was gebaseer op die ADACOR argitektuur as gevolg van die optimeringsvermoëns wat noodsaaklik was om die siklustyd van die stasie so laag as moontlik te hou. Die ontwerp en implementering van die fisiese konfigurasie en beheerstelsel van die stasie word in hierdie tesis beskryf. Die stasie was ontwerp om aan die vereistes van beide 'n HVS en die gevallestudie te voldoen. As gevolg van die beperkings van die IEC 61131-3 programmeringstale, is dinamiese instansiëring van holons nie moontlik nie, en 'n metode is ontwikkelom dinamiese taakholons na te boots. Deur gebruik te maak van die "embedded PC" se vermoë om meervoudige PLCs terselfdetyd te hanteer, kan elke holon tipe in sy eie "thread" loop. Die ontwikkelde stelsel en die stasie is geëvalueer in 'n laboratorium deur middel van eksperimente. Die evaluering van die beheerstelsel in hierdie tesis bewys dat 'n HVS geskep kan word, in die konteks van ‘n stasiebeheerder, deur IEC 61131-3 en tegnologie wat wyd in die industrie aanvaar word, te gebruik mits die hardeware-platform wat gebruik word toelaat dat verskeie PLCs terselfde tyd op een beheerder kan loop. Die beheerbenadering wat geskep is in hierdie tesis kan gebruik word om stasie- beheerstelsels te skep wat optimale siklus tye, die voordele van 'n HVS en die voordele van industrie-aanvaarde tegnologie bied.

Vehicular Ad hoc Networks (VANET) is a wireless ad-hoc network that includes two types of communications, Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I). In VANET there are two types of messages. The first type is the event-driven messages that are only triggered in case of emergency. The second type is the periodical messages named beacons that are exchanged frequently between vehicles. A beacon message contains basic information about the sending vehicle such as id, location and velocity. Beacons are frequently exchanged to increase the cooperative awareness between vehicles. Increasing beacon frequency helps increasing neighborhood awareness and improving information accuracy. However, this causes more congestion in the network, specially when the number of vehicles increases. On the other hand, reducing beacon frequency alleviates network congestion, but results in out-dated information. In this dissertation, we address the aforementioned challenges and propose a number of smart beaconing protocols and evaluate their performance in di↵erent environments and network densities. The four adaptive beaconing protocols are designed to increase the cooperative awareness and information freshness, while alleviating the network congestion. All the proposed protocols take into account the most important aspects, which are critical to beaconing rate adaptation. These aspects include channel status, traffic conditions and link quality. The proposed protocols employ fuzzy logic-based techniques to determine the congestion rank, which is used to adjust beacon frequency. The first protocol considers signal to interference-noise ratio (SINR), number of neighboring nodes and mobility to determine the congestion rank and adjust the beacon rate accordingly. This protocol works well in sparse conditions and highway environments. The second protocol works well in sparse conditions and urban environments. It uses channel busy time (CBT), mobility and packet delivery ratio (PDR) to determine the congestion rank and adjust the beacon rate. The third protocol utilizes CBT, SINR, PDR, number of neighbors and mobility as inputs for the fuzzy logic system to determine the congestion rank and adjust the beacon rate. This protocol works well in dense conditions in both highway and urban environments. Through extensive simulation experiments, we established that certain input parameters are more e↵ective in beacon rate adaptation for certain environments and conditions. Based on this, we propose a high awareness and channel efficient scheme that adapts to di↵erent environments and conditions. First, the protocol estimates the network density using adaptive threshold function. Then, it looks at the spatial distribution of nodes using the quadrat method to determine whether the environment is highway or urban. Based on the density conditions and nodes distribution, the protocol utilizes the appropriate fuzzy input parameters to adapt the beaconing rate. In addition, the protocol optimizes the performance by adapting the transmission power based on network density and nodes distribution. Finally, an investigation of the impact of adaptive beaconing on broadcasting is conducted. The simulation results confirm that our adaptive beaconing scheme can improve performance of the broadcast protocols in terms of reachability and bandwidth consumption when compared to a fixed rate scheme. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

No description available.

<p>This report presents the results of a thesis project that surveys and designs about the issue “Feature Model for Adaptive Computing”. In this project, there are two main issues, first one is about the Feature Modeling, and the second is how to use this Feature Modeling for adaptive computing.</p><p>In this thesis report, at the beginning, we present the problem we expected to solve and introduce some background information, including the knowledge of feature model and adaptive computing. Then we explain our solution and evaluate this solution. At the end of this report, we give a short conclusion about our thesis project and feature work.</p>

published_or_final_version / abstract / Electrical and Electronic Engineering / Master / Master of Philosophy

This investigation focuses on configurable technologies, a term which refers to technologies that are highly parameterizable and are built from a range of components to meet the very specific requirements of a particular organization. They cannot be seen independently of their representations through external intermediaries who "speak" for the technology by providing images, descriptions, demonstrations, policies, templates and "solutions". I use the term technology-configuring mediation to refer to the process characterized by a socially constructed relationship between clients and consultants, where visions of how the technology should operate are negotiated. Configurable tools are well illustrated by ERP projects and represent an important trend in IS, drawing its popularity from the hope of benefiting from increased economies of scale and access to cumulative knowledge supposedly "embedded" into these technological artifacts. / From a critical interpretive perspective that combines ideas from structuration theory, social shaping views of technology and critical discourse analysis, this dissertation is based on an empirical investigation that spanned one year and is primarily organized in three papers. The first paper investigates the use of structuration theory in the IS field, asking: How can we successfully apply structuration theory in IS empirical research? Paper 1 contributes to the advancement of interpretive research methods by describing, analyzing and illustrating the ways IS scholars have used Giddens' theory in their research. In addition, it presents a repertoire of research strategies that may help overcome barriers to the empirical application of structurationist theory by dealing with three core elements: time, context and duality of technology. / The second paper discusses the rhetorical closure that often dominates discourses about IT, arguing that configurable technologies are social constructions and, to different degrees, are always open to change. Taking ERP projects as a typical illustration of configurable IT, Paper 2 describes a multilevel framework that identifies occasions for ERP package negotiation and change at three levels---segment, organization and individual---thereby breaking down the rhetorical closure that seems to dominate public debate. Paper 2 draws on structurationist and political streams of thinking about technology to set out a theoretical framework that contributes to advancing our knowledge of configurable IS phenomena. / The third paper addresses the question: How does the mediation process influence the negotiation between global principles and local contexts during the implementation of configurable IS, and how does such a negotiation influence the success of the implemented technology? Paper 3 provides a new understanding of configurable technology implementation. The structuring of a new configuration is seen as a mediation process where knowledge and power dependencies are created and recreated over time by consultants and clients, the entire process being bordered by internal and external constraints. Paper 3 recognizes different patterns of mediation and explains how these patterns affect the negotiation of global principles and local contexts as well as the project results. The study ends by identifying a collection of mediating strategies that are likely to improve the implementation of configurable IS.

Integrated optics as a platform for signal processing offers significant benefits such as large bandwidth, low loss, and a potentially high degree of reconfigurability. Silicon (Si) has unique advantages as a material platform for integration, as well as properties such as a strong thermo-optic mechanism that allows for the realization of highly reconfigurable photonic systems. Chapter 1 is devoted to the discussion of these advantages, and Chapter 2 provides the theoretical background for the analysis of integrated Si-photonic devices. The thermo-optic property of Si, while proving extremely useful in facilitating reconfiguration, can turn into a nuisance when there is a need for thermally stable devices on the photonic chip. Chapter 3 presents a technique for resolving this issue without relying on a dynamic temperature stabilization process. Temperature-insensitive (or “athermal”) Si microdisk resonators with low optical loss are realized by using a polymer overlayer whose thermo-optic property is opposite to that of Si, and TiO2 is introduced as an alternative to polymer to deal with potential CMOS-compatibility issues. Chapter 4 demonstrates an ultra-compact, low-loss, fully reconfigurable, and high-finesse integrated photonic filter implemented on a Si chip, which can be used for RF-photonic as well as purely optical signal processing purposes. A novel, thermally reconfigurable reflection suppressor is presented in Chapter 5 for on-chip feedback elimination which can be critical for mitigating spurious interferences and protecting lasers from disturbance. Chapter 6 demonstrates a novel device for on-chip control of optical fiber polarization. Chapter 7 deals with select issues in the implementation of Si integrated photonic circuits. Chapter 8 concludes the dissertation.

Thesis (M.S.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (Ph.D.)--University of Melbourne, Dept. of Electrical and Electronic Engineering, 2010. / Typescript. Includes bibliographical references (p. 177-187)