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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.
141

A Real Time Fault Detection and Diagnosis System for Automotive Applications

doghri, ahmed January 2019 (has links)
Since its inception in the nineteenth century, the Internal Combustion Engine (ICE) remains the most prevalent technology in transportation systems to date. In order to minimize emissions, it is important that ICE is operated according to its optimized design conditions. As such, condition monitoring and Fault Detection and Diagnosis (FDD) tools can play an important role in detecting conditions that would affect the operability of the engine. In this research, different signal-based Fault Detection and Diagnosis (FDD) techniques are researched and implemented for fault condition monitoring of ICE. The implementation of prognostics for the engine in an automated form has important consequences that include cost savings, increased reliability, reduction of GHG emissions, better safety, and extended life for the vehicle. In this research, in order to carry out FDD onboard, a low-cost and flexible internet-based data-acquisition system (DAQ) was designed and implemented. The main part of the system is an embedded hardware running a full desktop version of Linux. This sensory system leverages the positive aspects of both real-time and general-purpose architectures to ensure engine monitoring at high sampling rates. Unlike other commercial DAQ systems, the software of this device is open-source, free of charge, and highly expandable to suit other FDD applications. In addition to data collection at high sampling rates, the FDD system includes advanced FDD strategies. The Fault Detection and Diagnosis strategies considered use a combination of Fourier Transforms (FT), Wavelet Transforms (WT), and Principal Component Analysis (PCA). Meanwhile, Fault Classification was carried using Neural Networks consisting of the Multi-Layer Perceptron (MLP). Three strategies were comparatively considered for the training of the Neural Network (NN), namely the Levenberg-Marquardt (LM), the Extended Kalman Filter (EKF), and the Smooth Variable Structure Filter (SVSF) techniques. The proposed FDD system was able to achieve 100% accuracy in classifying a set of engine faults. / Thesis / Master of Applied Science (MASc)
142

Development of the second-generation IMTS (Intelligent Monitoring and Trending System) and WOT (Wizard of Tech) expert system for rotating machinery

Pawtowski, E. C. 02 October 2008 (has links)
IMTS and WOT form a PC-based hardware and software system designed to continuously monitor large numbers of rotating machinery, evaluate each machine's condition through a series of user-definable standards, and alert operators to potential problems. This system requires a rack of data acquisition equipment located near the machines being monitored and a PC that can be located remotely. This system has been tested under actual plant conditions at the Virginia Tech Power Plant. The software operates under Windows 3.1, and allows data to be acquired and evaluated simultaneously. This thesis discusses the development of this system over earlier versions and the installation procedures and first runs at the Power Plant. It discusses in detail the operation of some of the main programs that comprise the Intelligent Trending and Expert System. / Master of Science
143

Time-resolved crystallography using the Hadamard transform

Yorke, Briony A., Beddard, G.S., Owen, R.L., Pearson, A.R. 10 May 2014 (has links)
Yes / We describe a method for performing time-resolved X-ray crystallographic experiments based on the Hadamard transform, in which time resolution is defined by the underlying periodicity of the probe pulse sequence, and signal/noise is greatly improved over that for the fastest pump-probe experiments depending on a single pulse. This approach should be applicable on standard synchrotron beamlines and will enable high-resolution measurements of protein and small-molecule structural dynamics. It is also applicable to other time-resolved measurements where a probe can be encoded, such as pump-probe spectroscopy. / Wellcome Trust 4-year PhD program “The Molecular Basis of Biological Mechanisms” 089312/Z/09/Z. This work was also supported by the EPSRC Award “Dynamic Structural Science at the Research Complex at Harwell” EP/I01974X/1 and by BBSRC Award BB/H001905/1.
144

Defining Stress Changes Ahead of a Tunnel Face and Design of a Data Acquisition System

Murphy, Michael M. 05 January 2006 (has links)
With increasing world population, demand for underground construction is expected to accelerate in the future. Design of tunnels in rock is still largely empirical, while rock failure in underground mines and tunnel construction continues to claim lives. A seismic method to aid in increasing safety during excavation is tomography. Seismic tomography is a non-invasive technique to map the stress changes induced by mining ahead of the active face. Seismic tomography maps the velocity distributions of elastic waves traveling through a rock mass. The velocity distributions mapped in the tomograms can relate to anomalies in the rock such as fracture zones and highly concentrated stresses. In order to develop a relationship between stress and elastic wave velocity, laboratory tests in a controlled environment are required. In the current study tomographic tests were conducted on Berea sandstone and Five Oaks limestone samples. The stress redistribution in the sandstone samples could be imaged by mapping velocity distributions. On an unconfined test the sandstone sample acted much like a coal mine pillar where the stress redistributes to the least confined area. On a sandstone test where the sample was indented by a steel platen the velocity contrast was seen directly under the load and the velocity remained almost unchanged over the rest of the sample. For the limestone tests, the stress redistribution could not be mapped in the tomograms. The ability to map the stress distribution in the tomograms were attributed to the elastic and non-elastic characteristics of the stress-strain curve. For sandstone, a porous rock, the stress redistribution could be mapped and for limestone, a stiff rock, the stress redistribution could not be mapped. A field data acquisition system to apply tomography to ground control problems in a mine was designed and calibrated. Data acquisition hardware were assembled and programmed in LabVIEW to collect seismic data in a mine. The design of a geophone array that will fit into a miniature 5.08 cm (2 in) diameter borehole is presented. / Master of Science
145

Design of Power Converter and Wireless Data Acquisition System for TEG Energy Harvester

Xing, Shaoxu 01 November 2016 (has links)
In order to avoid the accidents like Fukushima Disaster and monitor the operation status of nuclear power plant, a wireless sensor system which is powered by the Thermoelectric Generator (TEG) Energy Harvester is designed and built. Meanwhile, a power converter circuit has also been designed to converter the output voltage of TEG Energy Harvester to a DC voltage to charge the battery or power the application systems. Several prototypes based on this power converter circuit have been built for Thermoelectric Generator (TEG) energy harvester and tested in both working and laboratory conditions. The reliability of the TEG Energy Harvester system in the gamma radiation environment has been examined in the experiments. Based on the experiments results, the design was optimized. And an optimized Maximum Power Point Tracking algorithm has also been applied in the prototype to extract the maximum power from the TEG Energy Harvester in all conditions. The TEG Energy Harvester system would be greatly simplified as a new type of sensor will be applied. The design of the signal conditioning circuit for this sensor has also been presented. / Master of Science / In this work, a comprehensive electronic systems for Thermoelectric Generator (TEG) Energy Harvester was designed and built. The system consists of two parts. One part is a converter circuit which can regulate the output voltage of the energy harvester and charge the battery efficiently while the other part is data acquisition and wireless communication system, which can collect data via different kinds of sensors and send the data out with the help of wireless communication modules. The prototype of the system was tested with the actual working conditions in the laboratory experiments and later optimized and improved based on the experiments results. An optimized Maximum Power Point Tracking algorithm was applied in the control of the power converter to ensure that the TEG Energy Harvester can output the maximum power in all conditions. Also, a new type of sensor was also developed for future system simplify and improvement.
146

An Integrated Data Acquisition System for Parachute Development and Qualification Testing

Starbuck, Philip 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / The development and qualification of personnel and cargo aerial delivery parachute systems present unique challenges to the instrumentation and data analysis engineers. Some of the areas that must be addressed include: a) system must be low in cost, b) system often has to be operated on ranges that have limited telemetry or other range instrumentation and support (i.e. commercial skydiving centers), c) system is often rigged and operated by parachute support personnel and test jumpers rather than instrumentation engineers, and d) system must be able to be reconfigured in the field to support a variety of test card requirements during a typical test day, e) data must be available for review and the system be prepared for the next test within a few minutes of parachute recovery, and f) system must withstand ground impact velocities as high as 50 ft/sec (15.24 m/sec) without damage. This paper describes such a system as it is being used for the development and qualification testing of a number of parachute systems for sport skydiving, military personnel, as well as cargo parachute systems. This modular system has been developed as a result of previous experience in other parachute development and qualification projects to address the need for a flexible Data Acquisition System (DAS) system that meets the above requirements. This paper describes some of the tools used to meet these requirements.
147

AIRBORNE DATA ACQUISITION SYSTEM FOR THE RAH-66 COMANCHE AIRCRAFT

Cebik, James A., Connor, William J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The RAH-66 Comanche flight test program required a state of the art Airborne Data Acquisition System consisting of: 1) A modular distributed system that uses a series of software programmable building blocks capable of signal conditioning all types of sensors. 2) A digital multiplexing system capable of combining various types of digital streams at high rates including Synchronous and Asynchronous PCM, MIL-STD-1553B, and RS-422 data streams. 3) A Data Combiner Unit that accepts synchronous PCM data streams from one to eight sources at 4 MBPS or less and a frame size of up to 8128 words each that outputs four independent PCM streams at 8 MBPS or less and a frame size of up to 16384 words. 4) A Data System Control Unit that controls the tape recorder, serves as the interface to the Pilot’s Control Unit and monitors/reports status of the data acquisition system to the Pilots Control Unit. 5) An Airborne Computer that provides the control and interface to the pilot & copilot instrumentation displays. 6) A Cockpit Instrumentation Pilot Display System consisting of a Main Unit Multi- Function Display, a Load Factor/Hub Moment Display and a Right Wing Flight Control Position Display. The Main Unit Multi-Function Display has the capability to display multiple graphic pages generated by the Airborne Computer. 7) The ability to record high speed avionics buses from the (Mission Equipment Package) MEP such as MIL-STD-1553B, (High Speed Data Bus) HSDB, (Processor Interconnect) PI Bus, (Data Flow Network) DFN and PCM utilizing the Ampex DCRsi-107 Tape Recorder.
148

Evaluation of gigabit links for use in HEP trigger processing

Anderson, Christopher R. January 1999 (has links)
No description available.
149

Evaluation of Protocols for Transfer of Automotive Data from an Electronic Control Unit / Utvärdering av protokoll för överföring av fordonsdata från en styrenhet

Lööf, Sam January 2014 (has links)
Nowadays almost all motorized vehicles use electronic control units (ECUs) to control parts of a vehicle’s function. A good way to understand a vehicle’s behaviour is to analyse logging data containing ECU internal variables. Data must then be transferred from the ECU to a computer in order to study such data. Today, Keyword Protocol (KWP) requests are used to read data from the ECUs at Scania. The method is not suitable if many signals should be logged with a higher transfer rate than the one used today. In this thesis, communication protocols, that allow an ECU to communicate with a computer, are studied. The purpose of this master’s thesis is to examine how the transfer rate of variables from Scania’s ECUs to a computer can become faster compared to the method used today in order to get a more frequent logging of the variables. The method that was chosen was implemented, evaluated and also compared to the method used today. The busload, total CPU load and CPU load for the frequency used during the experiments, 100 Hz, was also examined and evaluated. The experiments performed show that the method chosen, data acquisition (DAQ) with CAN Calibration Protocol (CCP), increased the transfer rate of the internal ECU variables significantly compared to the method using KWP requests. The results also show that the number of signals have a major impact on the busload for DAQ. The busload is the parameter that limits the number of signals that can be logged. The total CPU load and the CPU load for 100 Hz are not affected significantly compared to when no transmissions are performed. Even though the busload can become high if many variables are used in DAQ, DAQ with CCP is preferable over KWP requests. This is due to the great increase in transfer rate of the ECU internal variables and thus a great increase in the logging frequency. / Nuförtiden används styrenheter (ECUer) för att styra delar av ett fordons funktion i så gott som alla motoriserade fordon. Ett bra sätt att förstå ett fordons beteende är att analysera loggningsdata som innehåller interna styrenhetsvariabler. Data måste då överföras från styrenheten till en dator för att data ska kunna studeras. Idag används Keyword Protocol-förfrågningar (KWP-förfrågningar) för att läsa data från Scanias styrenheter. Metoden är inte lämplig om man vill logga många variabler med en högre överföringshastighet än den som används idag. I detta examensarbete studeras kommunikationsprotokoll som tillåter en styrenhet att kommunicera med en dator. Examensarbetets syfte är undersöka hur överföringshastigheten av variablerna, från Scanias styrenheter till en dator, kan ökas jämfört med den metod som används idag för att få en mer frekvent loggning av variablerna. Metoden som valdes implementerades, utvärderades och jämfördes med metoden som används idag. Busslasten, totala CPU-lasten och CPU-lasten för den frekvens som användes under experimenten 100 Hz har också undersökts och evaluerats. De utförda experimenten visar att den valda metoden, data acquisition (DAQ) med CAN Calibration Protocol (CCP), ökade överföringshastigheten av de interna styrenhetsvariablerna betydligt jämfört med metoden KWP-förfrågningar. Experimenten visar också att antalet signaler har stor inverkan på busslasten för DAQ. Busslasten är den parameter som begränsar antalet signaler som kan loggas. Den totala CPU-lasten och CPU-lasten för 100 Hz påverkas inte betydligt jämfört med när inga överföringar görs. DAQ med CCP är att föredra framför KWP-förfrågningar även om busslasten blir hög för DAQ då den stora ökningen i överföringshastighet av de interna styrenhetsvariablerna medför en mer frekvent loggning av variablerna.
150

A simulative analysis of the robustness of Smart Grid networks and a summary of the security aspects

Kubler, Sarah Marie January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / Caterina M. Scoglio / The need for reliable and quick communication in the power grid is growing and becoming more critical. With the Smart Grid initiative, an increasing number of intelligent devices, such as smart meters and new sensors, are being added to the grid. The traffic demand on the communications network increases as these new devices are being added. This can cause issues such as longer delay, dropped packets, and equipment failure. The power grid relies on this data to function properly. The power grid will lose reliability and will not be able to provide customers with power unless it has correct and timely data. The current communications network architecture needs to be evaluated and improved. In this thesis, a simulator program is developed to study the communications network. The simulation model is written in C++ and models the components of the communications network. The simulation results provide insight on how to design the communications network in order for the system to be robust from failures. We are using the simulator to study different topologies of the communications network. The communications network often has a simular topology to the power grid. This is because of right-a-ways and ownership of equipment. Modifying the topology of the communications network slightly can improve the performance of the network. Security of the communications network is a very important aspect. There is a risk of successful attacks on the communications network without the implementation of security protocols. Attacks can come from malicious users of the communications network or from entities outside the network. These attacks may lead to damaged equipment, loss of power to consumers, network overload, loss of data, and loss of privacy. This thesis presents a short overview of the major issues related to the security of the communications network. The department of Electrical and Computer Engineering (ECE) at Kansas State University (K-State) is working on developing a Smart Grid lab. Burns and McDonnell has collaborated with the ECE department at K-State to develop the Smart Grid Lab. This lab will be located inside of the ECE department. The lab will consist of both power grid equipment and network communication equipment. This thesis describes similar labs. It then describes the initial plan for the lab, which is currently in the planning stage.

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