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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The Development of Hardware Multi-core Test-bed on Field Programmable Gate Array

Shivashanker, Mohan 24 March 2011 (has links)
The goal of this project is to develop a flexible multi-core hardware test-bed on field programmable gate array (FPGA) that can be used to effectively validate the theoretical research on multi-core computing, especially for the power/thermal aware computing. Based on a commercial FPGA test platform, i.e. Xilinx Virtex5 XUPV5 LX110T, we develop a homogeneous multi-core test-bed with four software cores, each of which can dynamically adjust its performance using software. We also enhance the operating system support for this test platform with the development of hardware and software primitives that are useful in dealing with inter-process communication, synchronization, and scheduling for processes on multiple cores. An application based on matrix addition and multiplication on multi-core is implemented to validate the applicability of the test bed.
12

Komunikační rozhraní pro testbed I4.0 / Communication Interface for Industry 4.0 testbed

Magáth, Marek January 2020 (has links)
This diploma thesis deals with the creation of a general communication interface between the smart product and process cells within test bed Barman. The aim is to create distributed production according to the Industry 4.0 concept, where each product manages it’s production itself. The first part deals with the analysis of test bed, where are discussed requirements and method of production. Then with the selection of a communication protocol that would meet Industry 4.0 and distributed control requirements. The result of the research was OPC UA communication protocol. Using this protocol, the product and the process cell will communicate with each other. I chose the appropriate implementation for the selected protocol to be used for creating communication modules of the product and the process cell. Production data will be stored in an RFID chip located in the product. Part of the work is devoted to creation this data structure, which contains the recipe as well as production state data. Creation of RFID reader is the work of another student, with whom I solved the method of data exchange between application of the reader and the communication module of the product. When creating a communication module of the process cell, I solved the design of an information model that describes the entire process cell, and the dynamic creation of nodes in the address space. I have mentioned a few examples of how I worked with a selected implementation of OPC UA and how I used it in both applications. I implemented decentralized search of another process cells in the local network. This feature was easy to implement with OPC UA, specifically with the LDS-ME service. I solved the control of production for the communication module of the product and method of communication with the process cell. And in the last part I deal with manual, which describes how to compile projects correctly, specifically on the Linux operating system, and I have described a way to test the whole solution together with the results.
13

Design of a Testbed for Haptic Devices Used by Surgical Simulators / Konstruktion av en testbänk för haptiska instrument använda för simulering av kirurgi

Udvardy, Zoltán January 2017 (has links)
Nowadays surgery simulations are aiming to apply not just visual effects but forcefeedback as well. To carry out force feedback, haptic devices are utilized that are mostlycommercial products for general purposes. Some of the haptic device features are moreimportant than others in case of surgery simulator use. The precision of the output forcemagnitude is one such property. The specifications provided by haptic devicemanufacturers are lacking details on device characteristics, known to cause difficulties inplanning of accurate surgery simulations.This project shows the design of a testbed that is capable of measuring the precision ofoutput forces within the haptic devices’ workspace. With the testbed, a set ofmeasurements can be run on different haptic devices, giving as a result a betterknowledge of the utilized device. This knowledge aids the design of more precise andrealistic surgery simulations.
14

Event and Intrusion Detection Systems for Cyber-Physical Power Systems

Adhikari, Uttam 14 August 2015 (has links)
High speed data from Wide Area Measurement Systems (WAMS) with Phasor Measurement Units (PMU) enables real and non-real time monitoring and control of power systems. The information and communication infrastructure used in WAMS efficiently transports information but introduces cyber security vulnerabilities. Adversaries may exploit such vulnerabilities to create cyber-attacks against the electric power grid. Control centers need to be updated to be resilient not only to well-known power system contingencies but also to cyber-attacks. Therefore, a combined event and intrusion detection systems (EIDS) is required that can provide precise classification for optimal response. This dissertation describes a WAMS cyber-physical power system test bed that was developed to generate datasets and perform cyber-physical power system research related to cyber-physical system vulnerabilities, cyber-attack impact studies, and machine learning algorithms for EIDS. The test bed integrates WAMS components with a Real Time Digital Simulator (RTDS) with hardware in the loop (HIL) and includes various sized power systems with a wide variety of implemented power system and cyber-attack scenarios. This work developed a novel data processing and compression method to address the WAMS big data problem. The State Tracking and Extraction Method (STEM) tracks system states from measurements and creates a compressed sequence of states for each observed scenario. Experiments showed STEM reduces data size significantly without losing key event information in the dataset that is useful to train EIDS and classify events. Two EIDS are proposed and evaluated in this dissertation. Non-Nested Generalized Exemplars (NNGE) is a rule based classifier that creates rules in the form of hyperrectangles to classify events. NNGE uses rule generalization to create a model that has high accuracy and fast classification time. Hoeffding adaptive trees (HAT) is a decision tree classifier and uses incremental learning which is suitable for data stream mining. HAT creates decision trees on the fly from limited number of instances, uses low memory, has fast evaluation time, and adapts to concept changes. The experiments showed NNGE and HAT with STEM make effective EIDS that have high classification accuracy, low false positives, low memory usage, and fast classification times.
15

Modeling and Testing of Bistable Waterbomb Base Configurations

Hanna, Brandon Holbrook 01 December 2014 (has links) (PDF)
Origami is making an impact in engineering as solutions to problems are being found by applying origami principles (eg. flat-foldability) and using specific crease patterns as inspiration. This thesis presents an in-depth analysis of a particular origami fold -- the waterbomb base -- to facilitate its use in future engineering problems. The watebomb base is of interest due to its familiarity to the origami community, simple topology (can be made by folding a single sheet of paper four times), scalability, generalizability, and interesting kinetic behavior. It can behave as a nonlinear spring as well as a one- or two-way bistable mechanism. This thesis presents models of the kinetic behavior of the traditional waterbomb base as well as some non-traditional variants to be used as tools in future development of waterbomb-base-inspired mechanisms. In all cases considered here, developability as well as rotational symmetry in both the geometry and motion of the mechanisms are assumed. The thesis provides an introduction to origami and reviews some of the ways in which it has been studied and applied in engineering fields. The waterbomb base is also presented as a specific origami fold with practical application potential. Models for the behavior of the traditional waterbomb base are introduced and its potential usefulness as a testbed for actuation methods is discussed. Models are developed for its kinematic and bistable behavior, including the forces needed to transition between stable states. These models are validated by comparison to physical prototype testing and finite element analysis. The thesis introduces the generalized waterbomb base (WB) and generalized split-fold waterbomb base (SFWB). The WB maintains the pattern of alternating mountain and valley folds around the vertex but in this generalized case any even number of folds greater than or equal to 6 is allowed. An SFWB is created by splitting each fold of a WB into two “half folds”, effectively doubling the number of folds and links but halving the deflection at each fold. The same models that were developed for the traditional waterbomb base are developed for the WB and the SFWB and a few potential applications are discussed.
16

Adaptive manufacturing: dynamic resource allocation using multi-agent reinforcement learning

Heik, David, Bahrpeyma, Fouad, Reichelt, Dirk 13 February 2024 (has links)
The global value creation networks have experienced increased volatility and dynamic behavior in recent years, resulting in an acceleration of a trend already evident in the shortening of product and technology cycles. In addition, the manufacturing industry is demonstrating a trend of allowing customers to make specific adjustments to their products at the time of ordering. Not only do these changes require a high level of flexibility and adaptability from the cyber-physical systems, but also from the employees and the supervisory production planning. As a result, the development of control and monitoring mechanisms becomes more complex. It is also necessary to adjust the production process dynamically if there are unforeseen events (disrupted supply chains, machine breakdowns, or absences of staff) in order to make the most effective and efficient use of the available production resources. In recent years, reinforcement learning (RL) research has gained increasing popularity in strategic planning as a result of its ability to handle uncertainty in dynamic environments in real time. RL has been extended to include multiple agents cooperating on complex tasks as a solution to complex problems. Despite its potential, the real-world application of multi-agent reinforcement learning (MARL) to manufacturing problems, such as flexible job-shop scheduling, has been less frequently approached. The main reason for this is most of the applications in this field are frequently subject to specific requirements as well as confidentiality obligations. Due to this, it is difficult for the research community to obtain access to them, which presents substantial challenges for the implementation of these tools. ...
17

Modeling And Testing Of An Instantaneous Overcurrent Relay Using Vtb And Vtb-Rt

Patel, Daxa 05 August 2006 (has links)
This thesis explores the application of the Virtual Test Bed (VTB) and its real-time extension, VTB-RT, for protective relay modeling, simulation, and testing. An instantaneous overcurrent relay model was developed in VTB for a transmission line protection. The same relay model was built in Matlab/Simulink for validation purposes. Both models were tested for various fault conditions on a radial power system and results were compared. Moreover, a low cost real-time Hardware-In-the-Loop (HIL) simulation platform was implemented for relay model testing using VTB-RT and public domain software packages such as Real-Time Application Interface (RTAI), Comedi, and Comedilib, and notebook computer hardware. The applicability of VTB-RT was verified through an open-loop simulation and a HIL simulation of a simple dynamic system using dSPACE as the control hardware and NI DAQCard-6062E as the input/output interface. Simulation results are presented showing the effectiveness of the VTB-RT platform for model testing.
18

8×1 Antenna Array System for Uplink Beamforming in LTE-A and 5G NR

Haroun, Mohammad Hassan 21 October 2019 (has links)
[ES] La tecnologia en fases de paquets es va convertir en dècades enrere en la indústria del radar. Avui en dia, la matriu de fases o la formació de bigues s'està convertint en una necessitat per a la comunicació digital. L'explotació d'un sistema de transmissió de feixos ajudarà a reduir el consum total d'energia de les estacions base i dels equips d'usuaris. També permetrà al servei oferir dades molt més elevades i millorar la qualitat del servei. La investigació sobre la comunicació digital i la comunicació requereix una antena i un maquinari compatible. El maquinari hauria de ser capaç de gestionar diferents escenaris i enfocaments per a problemes de comunicació mòbil. Hi ha diversos sistemes utilitzats per a la investigació de la formació de bigues, especialment per a la comunicació mòbil. Aquests sistemes pateixen de diverses deficiències. Són cares d'implementar, no adaptatives i fixades a una arquitectura relacionada amb determinat algorisme de generació de feixos o amb un nombre d'elements d'array fix. En aquesta tesi es proposa un nou sistema de matrius per fases. Aquest sistema es podria explotar per a la investigació en problemes de comunicació mòbil o radar. Està compost per una xarxa d'antenes planes de 8x1, canals de conversió de RF a banda base i processador de banda base. Es fa una estimació de la transformació de fases i de la DOA en mostres digitals de banda base. Això proporciona al sistema dinàmica quant als algorismes provats. Amb aquesta finalitat, es fan servir juntes SDR àgils per adquirir senyals de la matriu d'antenes i convertir-les en fluxos de dades digitals. Els fluxos de dades es processen després en un processador de banda base basat en FPGA. A més de ser baixos en costos i assequibles per part de petits instituts d'investigació i investigacions independents, el sistema es pot ajustar per portar més elements de matriu d'antenes. La matriu monopola plana de 8x1 està dissenyada, simulada i mesurada. Es combinen i descriuen les característiques d'impedància i de radiació. Els SDR s'introdueixen i es calibren per al funcionament de diversos elements i s'introdueixen els mètodes de calibratge per incerteses de fase i amplitud. El rendiment global del sistema es prova mitjançant diferents algorismes de formulació de feixos i algorismes de direcció d'estimació d'arribada. Els resultats de la mesura mostren que el sistema és fiable. S'aconsegueix un model de beamformació amb bona resolució i un rebuig elevat de la interferència. La estimació de la direcció d'arribada és precisa. / [CA] La tecnología de matriz en fase hizo una rotación en la industria del radar hace décadas. Hoy en día, la matriz en fase, o formación de haz, se está convirtiendo en una necesidad para la comunicación digital. La explotación de la formación de haz ayudaría a reducir el consumo de energía general de las estaciones base y el equipo del usuario. También permitirá que el servicio brinde datos mucho más altos y mejore la calidad del servicio. La investigación sobre la formación y comunicación de haces digitales requiere un conjunto de antenas y hardware compatible. El hardware debe ser capaz de manejar diferentes escenarios y enfoques para problemas de comunicación móvil. Hay varios sistemas utilizados para la investigación de conformación de haz, especialmente para la comunicación móvil. Estos sistemas sufren de varias deficiencias. Son costosos de implementar, no adaptativos y fijos a una arquitectura relacionada con cierto algoritmo de conformación de haz o con un número de elementos de arreglo fijo. En esta tesis, se propone un nuevo sistema matricial por fases. Este sistema podría ser explotado para la investigación en comunicaciones móviles o problemas de radar. Está compuesto por un conjunto de antenas planas de 8x1, canales de conversión de RF a banda base y procesador de banda base. La formación de haz y la estimación de DOA se realizan en muestras digitales de banda base. Esto proporciona al sistema dinamismo con respecto a los algoritmos probados. Para ese propósito, las tarjetas SDR ágiles se utilizan para adquirir señales de la red de antenas y convertirlas en flujos de datos digitales. Los flujos de datos se procesan en un procesador de banda base basado en FPGA. Además de ser de bajo costo y asequible para los pequeños institutos de investigación e investigaciones independientes, el sistema se puede ajustar para llevar más elementos de la red de antenas. El conjunto monopolo plano 8x1 está diseñado, simulado y medido. La correspondencia de impedancia y las características de radiación se representan y describen. Los SDR se introducen y se calibran para la operación de elementos múltiples y se introducen los métodos de calibración para las incertidumbres de fase y amplitud. El rendimiento general del sistema se prueba mediante diferentes algoritmos de conformación de haz y algoritmos de estimación de la dirección de llegada. Los resultados de las mediciones muestran que el sistema es confiable. Se logra una conformación de haz con buena resolución y alto rechazo de interferencia. Dirección de estimación de la llegada es precisa. / [EN] Phased array technology made a turnover in radar industry decades ago. Nowadays, phased array, or beamforming, is becoming a necessity for digital communication. Exploiting beamforming would help in reducing the overall power consumption of base stations and user equipment. It will also enables the service to provide much higher datarates and enhance the quality of service. Research on digital beamforming and communication requires antenna array and compatible hardware. The hardware should be capable of handling different scenarios and approaches for mobile communication problems. There are several systems used for beamforming research especially for mobile communication. These systems suffer from several deficiencies. They are either expensive to implement, not adaptive and fixed to an architecture related to certain beamforming algorithm or with fixed array elements number. In this thesis, a new phased array system is proposed. This system could be exploited for research in mobile communication or radar problems. It is composed of 8x1 planar antenna array, RF to baseband conversion channels and base band processor. Beamforming and DOA estimation is done on base band digital samples. This provides the system with dynamicity regarding tested algorithms. For that purpose, agile SDR boards are used to acquire signals from antenna array and convert them to digital data streams. Data streams are then processed in an FPGA based base band processor. In addition to being low in cost and affordable by small research institutes and freelancing researches, the system can be adjusted to carry more antenna array elements. The 8x1 planar monopole array is designed, simulated and measured. Impedance matching and radiation characteristics are plotted and described. SDRs are introduced and calibrated for multi-element operation and calibration method for phase and amplitude uncertainties are introduced. Overall system performance is tested by different beamforming algorithms and direction of arrival estimation algorithms. Measurement results show that the system is reliable. Beamforming with good resolution and high interference rejection is achieved. Direction of arrival estimation is accurate. / Haroun, MH. (2019). 8×1 Antenna Array System for Uplink Beamforming in LTE-A and 5G NR [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/129852
19

Vehicle highway automation

Challa, Dinesh Kumar January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Gurdip Singh / Vehicle Highway Automation has been studied for several years but a practical system has not been possible because of technology limitations. New advances in sensing and communication technology have now brought a realistic system within reach. This paper proposes a Co-Operative Vehicle Highway Automation System for automating traffic information gathering and decision making in a vehicle on a highway which is cost effective and near to real life implementation. Co-Operative Vehicle-Highway Automation System is the system which is implemented by technology on-board a vehicle and also on the intelligent infrastructure technology along a highway. Vehicle Automation, Collision Prevention and Avoidance, Route Guidance, Highway Information System, Vehicle tracking, and Traffic surveillance are some applications which can be implemented in the Co-Operative Vehicle-Highway Automation System. Implementing Vehicle Highway Automation System will provide an ameliorated level of road transportation. The possible benefits to society and individuals are many in terms of time, safety, comfort and overall travel quality.
20

A Novel Approach to Determining Real-Time Risk Probabilities in Critical Infrastructure Industrial Control Systems

Elrod, Michael 01 January 2017 (has links)
Critical Infrastructure Industrial Control Systems are substantially different from their more common and ubiquitous information technology system counterparts. Industrial control systems, such as distributed control systems and supervisory control and data acquisition systems that are used for controlling the power grid, were not originally designed with security in mind. Geographically dispersed distribution, an unfortunate reliance on legacy systems and stringent availability requirements raise significant cybersecurity concerns regarding electric reliability while constricting the feasibility of many security controls. Recent North American Electric Reliability Corporation Critical Infrastructure Protection standards heavily emphasize cybersecurity concerns and specifically require entities to categorize and identify their Bulk Electric System cyber systems; and, have periodic vulnerability assessments performed on those systems. These concerns have produced an increase in the need for more Critical Infrastructure Industrial Control Systems specific cybersecurity research. Industry stakeholders have embraced the development of a large-scale test environment through the Department of Energy’s National Supervisory Control and Data Acquisition Test-bed program; however, few individuals have access to this program. This research developed a physical industrial control system test-bed on a smaller-scale that provided an environment for modeling a simulated critical infrastructure sector performing a set of automated processes for the purpose of exploring solutions and studying concepts related to compromising control systems by way of process-tampering through code exploitation, as well as, the ability to passively and subsequently identify any risks resulting from such an event. Relative to the specific step being performed within a production cycle, at a moment in time when sensory data samples were captured and analyzed, it was possible to determine the probability of a real-time risk to a mock Critical Infrastructure Industrial Control System by comparing the sample values to those derived from a previously established baseline. This research achieved such a goal by implementing a passive, spatial and task-based segregated sensor network, running in parallel to the active control system process for monitoring and detecting risk, and effectively identified a real-time risk probability within a Critical Infrastructure Industrial Control System Test-bed. The practicality of this research ranges from determining on-demand real-time risk probabilities during an automated process, to employing baseline monitoring techniques for discovering systems, or components thereof, exploited along the supply chain.

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