Relevant bibliographies by topics / Signal conditioning / Dissertations / Theses
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Dissertations / Theses on the topic 'Signal conditioning'

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Published: 4 June 2021
Last updated: 6 September 2023

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1

Valero, Daniel. "Wireless Signal Conditioning." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc862776/.

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This thesis presents a new approach to extend and reduce the transmission range in wireless systems. Conditioning is defined as purposeful electromagnetic interference that affects a wireless signal as it propagates through the air. This interference can be used constructively to enhance a signal and increase its energy, or destructively to reduce energy. The constraints and limitations of the technology are described as a system model, and a flow chart is used to describe the circuit process. Remaining theoretical in nature, practical circuit implementations are foregone in the interest of elementary simulations depicting the interactions of modulated signals as they experience phase mismatch. Amplitude modulation and frequency modulation are explored with using both positive and negative conditioning, and conclusions to whether one is more suitable than the other are made.
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2

Medelius, Pedro J., Carl Hallberg, William E. Larson, and Dean Becker. "The Universal Signal Conditioning Amplifier." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/611746.

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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California
A state-of-the-art instrumentation amplifier capable of being used with most types of transducers has recently been developed at the Kennedy Space Center. This Universal Signal Conditioning Amplifier (USCA) can eliminate costly measurement setup time and troubleshooting, improve system reliability, and provide more accurate data than conventional amplifiers. The USCA can configure itself for maximum resolution and accuracy based on information read from a RAM chip attached to each transducer. Excitation voltages or currents are also automatically configured. The amplifier uses both analog and digital state-of-the-art technology with analog-to-digital conversion performed in the early stages to minimize errors introduced by offset and gain drifts in the analog components. A dynamic temperature compensation scheme has been designed to achieve and maintain 12-bit accuracy of the amplifier from 0 to 70E C. The digital signal processing section allows the implementation of digital filters up to 511th order. The amplifier can also perform real-time linearizations up to fourth order while processing data at a rate of 23,438 samples per second (23.438 kS/s). Both digital and analog outputs are available from the amplifier.
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3

Penharlow, David. "Signal Conditioning, the Next Generation." International Foundation for Telemetering, 1989. http://hdl.handle.net/10150/614701.

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International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California
This paper describes the changes in signal conditioning techniques used on flight test programs in recent years. Improved sensors require improved signal conditioning. Advanced distributed data acquisition systems, used on major flight test programs, move the signal conditioning closer to the sensor for improved performance and reduced wiring throughout the vehicle. These distributed systems use digital communication between the master controller and the remote conditioning units for improved accuracy and noise immunity. This requires sample- and-hold amplifiers, analog-to-digital converters, and serial encoder/decoders to be located at the signal conditioning location. The changes in signal conditioning designs are driven by the sensors, the architecture of the data acquisition systems, and by vehicle designs (smaller aircraft, smaller missiles, composite structures, and hypervelocity vehicles). A look at the signal conditioning technology employed in many of these systems as well as what is anticipated in the future is described in this paper.
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4

Gould, Lee. "Digital signal conditioning on multiprocessor systems." Thesis, Durham University, 1992. http://etheses.dur.ac.uk/5965/.

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An important application area of modem computer systems is that of digital signal processing. This discipline is concerned with the analysis or modification of digitally represented signals, through the use of simple mathematical operations. A primary need of such systems is that of high data throughput. Although optimised programmable processors are available, system designers are now looking towards parallel processing to gain further performance increases. Such parallel systems may be easily constructed using the transputer family of processors. However, although these devices are comparatively easy to program, they possess a general von Neumann core and so are relatively inefficient at implementing digital signal processing algorithms. The power of the transputer lies in its ability to communicate effectively, not in its computational capability. The converse is true of specialised digital signal processors. These devices have been designed specifically to implement the type of small data intensive operations required by digital signal processing algorithms, but have not been designed to operate efficiently in a multiprocessor environment. This thesis examines the performance of both types of processors with reference to a common signal processing application, multichannel filtering. The transputer is examined in both uniprocessor and multiprocessor configurations, and its performance analysed. A theoretical model of program behaviour is developed, in order to assess the performance benefits of particular code structures and the effects of such parameters as data block size. The transputer implementation is contrasted with that of the Motorola DSP56001 digital signal processor. This device is found to be much more efficient at implementing such algorithms on a single device, but provides limited multiprocessor support. Using the conclusions of this assessment, a hybrid multiprocessor has been designed. This consists of a transputer controlling a number of signal processors, communicating through shared memory, separating tiie tasks of computation and communication. Forcing the transputer to communicate through shared memory causes problems, and these have been addressed. A theoretical performance model of the system has been produced. A small system has been constructed, and is currently running performance test software.
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5

Cirineo, Tony. "Doppler Video Signal Conditioning, Theory of Operation." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611417.

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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
This paper describes some of the signal conditioning and processing circuits that were developed to reconstruct the doppler video signal from a radar receiver under test. The reconstructed doppler video signal is then digitized and put into a telemetry frame for transmission to a ground receiving station.
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6

Amprikidis, Michael. "Vibration sensing using piezoelectric devices and signal conditioning." Thesis, University of Manchester, 2004. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488086.

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7

Tate, Jeffrey J. "Automating Signal Conditioning Setup Through Integration with Sensor Information." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607535.

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International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Caterpillar Inc. has been testing construction and mining equipment using Computerized Analysis Vans for two decades. During our latest van upgrade, we chose to move to PCM/FM from FM/FM mainly to increase the channel count. We also replaced our old signal conditioning that used span and balance potentiometers with computer programmable signal conditioning. This new signal conditioning requires that the gain and balance point be calculated for every channel on each test. The formulas for these calculations depend on the sensor, the signal conditioning card used, and the test requirements. Due to the number and variety of machines tested at the Caterpillar Proving Grounds, these calculations needed to be automated. Using a few initial parameters and the information from our sensor calibration database, each channel’s balance point, gain, and expected slope are calculated. This system has increased productivity, accuracy, and consistency over manually calculating these parameters. This paper covers the sensor database, the calculated parameters and an overview of the way the system works.
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8

Byun, Albert Joon-Soo. "Analog signal conditioning design for a wireless data acquisition device." Connect to this title online, 2005. http://hdl.handle.net/1811/368.

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Thesis (Honors)--Ohio State University, 2005.
Title from first page of PDF file. Document formattted into pages: contains v, 28 p.; also includes graphics. Includes bibliographical references (p. 21-22). Available online via Ohio State University's Knowledge Bank.
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9

Lee, Jeffrey C. "Design Considerations for a Variable sample Rate Signal Conditioning Module." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606212.

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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California
Modern telemetry systems require flexible sampling rates for analog signal conditioning within telemetry encoders in order to optimize mission formats for varying data acquisition needs and data rate constraints. Implementing a variable sample rate signal conditioning module for a telemetry encoder requires consideration of several possible architectural topologies that place different system requirements on data acquisition modules within the encoder in order to maintain adequate signal fidelity of sensor information. This paper focuses on the requirements, design considerations and tradeoffs associated with differing architectural topologies for implementing a variable sample rate signal conditioning module and the resulting implications on the encoder system's data acquisition units.
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10

Kozmin, Kirill. "Data acquisition and signal conditioning for low power measurement systems /." Luleå : EISLAB, Department of Computer Sience and Electrical Engineering, Luleå University of Technology, 2008. http://epubl.ltu.se/1402-1544/2008/42/.

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11

Powell, David G. "How to Build a High Accuracy, 100 Channel, PCM Encoder for $29.95." International Foundation for Telemetering, 1992. http://hdl.handle.net/10150/611920.

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International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California
Pulse Code Modulation (PCM) Encoders are extensively used in instrumentation and telemetry systems. Commercially available encoders are available from several sources and vary in complexity depending on the application. Encoders often include analog signal conditioning, a system clock, and one or more digital input ports. Many of these systems also cost several thousand dollars and the cost goes up when high data accuracy of one or two percent is required. This paper describes a low cost approach which has been used in production telemetry applications with great success and which yields a PCM encoder with data accuracies of better than 2%.
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12

Gibson, David, N. B. Penrose, Michael Doerr, and Gary Borgen. "HSTSS-DAC CUSTOM INTEGRATED CIRCUITS FOR SUBMINIATURE PCM TELEMETRY AND SIGNAL CONDITIONING." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/608711.

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada
To meet specific test and evaluation requirements, the Hardened Subminiature Telemetry and Sensor Systems (HSTSS) program is addressing the miniaturization and ‘G’ hardening of telemetry components. Two custom Integrated Circuits (ICs) are in development to support the design of miniature Pulse Code Modulation (PCM) systems with up to 128 analog input channels. This paper describes the design and development of the custom IC chips of the HSTSS Data Acquisition Chipset (DAC). The original requirements, the roll of the Integrated Product Team (IPT), design decisions, a discussion of the additional features, and practical limitations of the Data Acquisition Chipset will be covered.
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13

Bower, Trent A. "Voltage Self-Amplification and Signal Conditioning for Enhanced Microbial Fuel Cell Performance." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374234731.

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14

DYRJAWOJ, NICOLAU. "Desenvolvimento de um amplificador isolador para analise de sinais dinamicos." reponame:Repositório Institucional do IPEN, 2003. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11104.

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Made available in DSpace on 2014-10-09T12:48:25Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:57:36Z (GMT). No. of bitstreams: 1 08984.pdf: 7815530 bytes, checksum: 2846bcddfb4f882d621deacbf8447f3e (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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15

Chang, Dah W. "ADVANCED AIRBORNE TEST INSTRUMENTATION SYSTEM (AATIS) PROGRAM SYSTEM OVERVIEW." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608875.

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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada
The Advanced Airborne Test Instrumentation System (AATIS), one of the major instrumentation systems in use today by the Department of Defense (DoD), was developed in the late 1980's to improve and modernize its predecessor - the Airborne Test Instrumentation System (ATIS). Use of AATIS, by not only the Air Force but the Navy and Army, has improved instrumentation commonality and interoperability across multiple test programs. AATIS, developed by the same manufacturer as the DoD Common Airborne Instrumentation System (CAIS), has a common bus structure - enabling cross utilization of many components which will ease transition from one system to another. The objective of this paper is to provide an overview on the Advanced ATIS System and its logistics support concept. For system description, an overview is presented on the airborne system and related ground support equipment. A brief description is given on the three levels of maintenance being used or planned for by the using activities. Finally, a projection is presented on the utilization of this system for the next 3 years.
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16

Agjee, F. M. D. E. (Faatima Moosa Dawood Ebrahim). "A wideband signal conditioning system for high voltage measurements using a transconductance topology." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51633.

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Thesis (MScEng)--Stellenbosch University, 2000.
ENGLISH ABSTRACT: Recent research has shown that standard substation capacitive voltage transformers (CVTs) and current transformers (CTs) can be used for the measurement of wideband high voltage phenomena by employing these apparatus in a transconductance topology. With this topology the voltage waveform can be obtained by integration of the ground return current in the earth straps of the CVT and the CT. This technique does, however, impose unique requirements on the amplification and integration instrumentation due to large dynamic range requirements and the strict offset specifications required for accurate integration. This thesis describes a programmable, wideband signal conditioning system for high voltage (HV) measurements using the transconductance topology. A suitable system topology, optimised to reduce the problems usually associated with grounding and electromagnetic interference (EMI) in HV environments, is proposed. This system consists of an analog signal conditioning subsystem, a digital signal conditioning subsystem and a high speed serial fibre-optic link. The analog signal conditioning subsystem conditions the signals from a sensor to levels suitable for the digitiser of the digital signal conditioning subsystem. The high bandwidth specification of the application made it necessary to consider both discrete and integrated implementation of the analog signal conditioning subsystem. Based on the simulated and laboratory test results of both implementations, the optimum design was chosen for the developed system. The digital signal conditioning subsystem, which performs the integration, as well as the serial optic-fibre link control logic was implemented using programmable logic array (PLA) technology. The digital data is transmitted across the fibre-optic link. This data is then converted back to an analog signal. Keywords: High voltage measurements, Transconductance topology.
AFRIKAANSE OPSOMMING: Onlangse navorsing het aangetoon dat standaard substasie kapasitiewe spanningstransformators en stroomtransformators gebruik kan word om wyeband hoogspanningsverskynsels te meet deur hierdie apparatuur in 'n transkonduktansie topologie aan te wend. Met hierdie topologie kan die spanningsgolfvorm verkry word deur die integrasie van die aardstrome in die aardverbindings van die kapasitiewe spanningstransformators en stroomtransformators. Hierdie tegniek stel egter unieke vereistes vir die versterkings- en integrasieinstrumentasie te wyte aan groot dinamiese bereik vereistes en die streng afset spesifikasies wat benodig word vir akkurate integrasie. Hierdie tesis beskryf 'n programmeerbare, wyeband seinkondisioneringstelsel vir hoogspanningsmetings deur van die transkonduktansie topologie gebruik te maak. 'n Geskikte stelseltopologie, wat geoptimiseer is om probleme, wat gewoonlik met aarding en elektromagnetiese interferensie in hoogspanningsomgewings geassosieer word, te verminder, is voorgestel. Die stelsel bestaan uit 'n analoog seinkondisioneringsubstelsel, 'n digitale seinkondisioneringsubstelsel en 'n hoëspoed seriële optiese vesel koppelvlak. Die analoog seinkondisioneringsubstelsel kondisioneer die seine vanaf 'n sensor na geskikte vlakke vir die versyferaar van die digitale seinkondisioneringsubstelsel. Die hoë bandwydte spesifikasie van die toepassing vereis die inagneming van beide diskrete en geïntegreerde implementerings van die analoog seinkondisioneringsubstelsel. Gebaseer op gesimuleerde en laboratorium toetsresultate van beide implementerings is die optimale ontwerp vir die ontwikkelde stelsel gekies. Die digitale seinkondisioneringsubstelsel wat die integrasie uitvoer, asook die seriële optiese vesel koppelvlak beheerlogika is geïmplementeer met behulp van programmeerbare logika skikking tegnologie. Die digitale data word gestuur oor die optiese vesel koppelvlak. Hierdie data word dan terug geskakel na 'n analoog sein. Sleutelwoorde: Hoogspanningsmetings, Transkonduktansie topologie.
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17

Gladney, Ed. "REDUCING MAINTENANCE COSTS ON THE SHUTTLE PROGRAM." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/607585.

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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
NASA and Lockheed Martin Telemetry & Instrumentation have jointly developed a new data acquisition system for the Space Shuttle program. The system incorporates new technologies which will greatly reduce manpower requirements by automating many of the functions necessary to prepare the data acquisition system for each shuttle launch. This new system, the Automated Data Acquisition System (ADAS), is capable of configuring itself for each measurement without operator intervention. The key components of the ADAS are the Universal Signal Conditioning Amplifier (USCA), the Transducer Electronic Data Sheet (TEDS), and the Data Acquisition System (DAS 450). The ADAS is currently being delivered and installed at Kennedy Space Center. NASA and Telemetry & Instrumentation are actively pursuing commercialization of the ADAS and its associated products which will be available during 1996.
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18

Jones, Sidney R. Jr. "The Common Airborne Instrumentation System Program Overview." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608869.

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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada
The Common Airborne Instrumentation System (CAIS) is being developed by the Department of Defense through a Tri-service Program Office. The goals of the program are two fold. The first is to develop an instrumentation system that will meet the needs of the Air Force, Army, and Navy into the next century. The system is designed to support a full breadth of applications from a few parameters to engineering and management and development programs. The second is to provide a system that is airframe as well as activity independent. To accomplish these goals, the CAIS consists of two segments. The airborne segment consists of a system controller with a suite of data acquisition units. The system is configured with only the units that are required. The ground segment consists of a variety of support equipment. The support equipment enables the user to generate formats, load/verify airborne units, perform system level diagnostics and more.
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19

Jie, Shi Chang. "Chinese New Telemetry Onboard System." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/611666.

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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California
This paper at first gives a brief historical review of Chinese development of telemetering onboard system and then make a brief introduction of new onboard system from several respects.
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20

Brown, Thomas R. Jr. "The Common Airborne Instrumentation System Program Management Overview." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/611744.

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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California
The Department of Defense, through a Tri-Service Program Office, is developing the Common Airborne Instrumentation System (CAIS) to promote standardization, commonality, and interoperability among aircraft test instrumentation systems. The advent of CAIS will change how the DoD test community conducts business. The CAIS program will allow aircraft test and evaluation facilities to utilize common airborne systems, ground support equipment, and technical knowledge for airborne instrumentation systems. The CAIS Program Office will conduct requirements analyses, manage system upgrades, and provide full life cycle support for this system. It is initiating several requirements contracts to provide direct ordering opportunities for DoD users to easily procure defined test instrumentation hardware. The program office will provide configuration management, inventory control, maintenance support, system integration, engineering support, and software management. In addition, it will continue to enhance the current system and develop new items to meet future requirements. Where existing equipment provides added benefit, this equipment may be added to the official CAIS family.
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21

Kolb, John. "SIGNAL PROCESSING ABOUT A DISTRIBUTED DATA ACQUISITION SYSTEM." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/605610.

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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California
Because modern data acquisition systems use digital backplanes, it is logical for more and more data processing to be done in each Data Acquisition Unit (DAU) or even in each module. The processing related to an analog acquisition module typically takes the form of digital signal conditioning for range adjust, linearization and filtering. Some of the advantages of this are discussed in this paper. The next stage is powerful processing boards within DAUs for data reduction and third-party algorithm development. Once data is being written to and from powerful processing modules an obvious next step is networking and decom-less access to data. This paper discusses some of the issues related to these types of processing.
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22

Asplund, Joakim. "Design and Implementation of a Sounding-Rocket Electric-Field Instrument : Signal Conditioning and Power Supplies." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187726.

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23

Miri, Seyed-Mehdi. "Modeling and fault detection in electromagnetic devices : applications to synchronous machines and signal conditioning systems /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487332636476273.

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24

Hicks, William T. "DIGITAL FILTERING OF MULTIPLE ANALOG CHANNELS." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/608360.

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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California
The traditional use of active RC-type filters to provide anti-aliasing filters in Pulse Code Modulation (PCM) systems is being replaced by the use of Digital Signal Processing (DSP). This is especially true when performance requirements are stringent and require operation over a wide environmental temperature range. This paper describes the design of a multi channel digital filtering card that incorporates up to 100 unique digitally implemented cutoff frequencies. Any combination of these frequencies can be independently assigned to any of the input channels.
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Hicks, William T. "An Analysis of Various Digital Filter Types for Use as Matched Pre-Sample Filters in Data Encoders." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/611585.

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International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada
The need for precise gain and phase matching in multi-channel data sampling systems can result in very strict design requirements for presample or anti-aliasing filters. The traditional use of active RC-type filters is expensive, especially when performance requirements are tight and when operation over a wide environmental temperature range is required. New Digital Signal Processing (DSP) techniques have provided an opportunity for cost reduction and/or performance improvements in these types of applications. This paper summarizes the results of an evaluation of various digital filter types used as matched presample filters in data sampling systems.
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26

Cardu, Roberto <1983&gt. "Analog Signal Acquisition and Conditioning for Near-Field Capacitive Communication and Active Combined EEG-EIT Monitoring." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4599/1/Cardu_Roberto_tesi.pdf.

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The work of the present thesis is focused on the implementation of microelectronic voltage sensing devices, with the purpose of transmitting and extracting analog information between devices of different nature at short distances or upon contact. Initally, chip-to-chip communication has been studied, and circuitry for 3D capacitive coupling has been implemented. Such circuits allow the communication between dies fabricated in different technologies. Due to their novelty, they are not standardized and currently not supported by standard CAD tools. In order to overcome such burden, a novel approach for the characterization of such communicating links has been proposed. This results in shorter design times and increased accuracy. Communication between an integrated circuit (IC) and a probe card has been extensively studied as well. Today wafer probing is a costly test procedure with many drawbacks, which could be overcome by a different communication approach such as capacitive coupling. For this reason wireless wafer probing has been investigated as an alternative approach to standard on-contact wafer probing. Interfaces between integrated circuits and biological systems have also been investigated. Active electrodes for simultaneous electroencephalography (EEG) and electrical impedance tomography (EIT) have been implemented for the first time in a 0.35 um process. Number of wires has been minimized by sharing the analog outputs and supply on a single wire, thus implementing electrodes that require only 4 wires for their operation. Minimization of wires reduces the cable weight and thus limits the patient's discomfort. The physical channel for communication between an IC and a biological medium is represented by the electrode itself. As this is a very crucial point for biopotential acquisitions, large efforts have been carried in order to investigate the different electrode technologies and geometries and an electromagnetic model is presented in order to characterize the properties of the electrode to skin interface.
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Cardu, Roberto <1983&gt. "Analog Signal Acquisition and Conditioning for Near-Field Capacitive Communication and Active Combined EEG-EIT Monitoring." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4599/.

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The work of the present thesis is focused on the implementation of microelectronic voltage sensing devices, with the purpose of transmitting and extracting analog information between devices of different nature at short distances or upon contact. Initally, chip-to-chip communication has been studied, and circuitry for 3D capacitive coupling has been implemented. Such circuits allow the communication between dies fabricated in different technologies. Due to their novelty, they are not standardized and currently not supported by standard CAD tools. In order to overcome such burden, a novel approach for the characterization of such communicating links has been proposed. This results in shorter design times and increased accuracy. Communication between an integrated circuit (IC) and a probe card has been extensively studied as well. Today wafer probing is a costly test procedure with many drawbacks, which could be overcome by a different communication approach such as capacitive coupling. For this reason wireless wafer probing has been investigated as an alternative approach to standard on-contact wafer probing. Interfaces between integrated circuits and biological systems have also been investigated. Active electrodes for simultaneous electroencephalography (EEG) and electrical impedance tomography (EIT) have been implemented for the first time in a 0.35 um process. Number of wires has been minimized by sharing the analog outputs and supply on a single wire, thus implementing electrodes that require only 4 wires for their operation. Minimization of wires reduces the cable weight and thus limits the patient's discomfort. The physical channel for communication between an IC and a biological medium is represented by the electrode itself. As this is a very crucial point for biopotential acquisitions, large efforts have been carried in order to investigate the different electrode technologies and geometries and an electromagnetic model is presented in order to characterize the properties of the electrode to skin interface.
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Brown, Thomas R. Jr. "THE COMMON AIRBORNE INSTRUMENTATION SYSTEM TEST PROGRAM." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/608403.

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International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada
The Department of Defense (DoD), through a Tri-Service Program Office, is developing the Common Airborne Instrumentation System (CAIS) to promote standardization, commonality, and interoperability among aircraft test instrumentation systems. The advent of CAIS will change how the DoD test community conducts business. The CAIS program will allow aircraft test and evaluation facilities to utilize common airborne systems, ground support equipment, and technical knowledge for airborne instrumentation systems. During the development of the CAIS, the Program Office will conduct a broad spectrum of tests: engineering design, acceptance, environmental qualification, system demonstration, and flight qualification. Each of these tests addresses specific aspects of the overall functional requirements and specifications. The use of test matrices enables the program office to insure each specific test covers the optimum requirements, and the combination of all testing efforts addresses the total system functional requirements.
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29

Hughes, Colan Evan. "New techniques in NMR spectroscopy." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297524.

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30

PENHARLOW, DAVID. "MICROMINIATURE DISTRIBUTED DATA ACQUISITION SYSTEM." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613485.

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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada
The new generation of advanced tactical aircraft and missiles places unique demands on the electronic and mechanical designs for flight test instrumentation, high bit rates, operating temperature range and system interconnect wiring requirements. This paper describes a microminiature PCM distributed data acquisition system with integral signal conditioning (MMSC) which has been used in advanced aircraft and missile flight testing. The MMSC system is constructed from microminiature, stackable modules which allow the user to reconfigure the system as the requirements change. A second system is also described which uses the same circuitry in hermetic hybrid packages on plug-in circuit boards.
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31

Riedel, Philipp, Mark J. Jacob, Dirk K. Müller, Nora C. Vetter, Michael N. Smolka, and Michael Marxen. "Amygdala fMRI Signal as a Predictor of Reaction Time." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-214196.

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Reaction times (RTs) are a valuable measure for assessing cognitive processes. However, RTs are susceptible to confounds and therefore variable. Exposure to threat, for example, speeds up or slows down responses. Distinct task types to some extent account for differential effects of threat on RTs. But also do inter-individual differences like trait anxiety. In this functional magnetic resonance imaging (fMRI) study, we investigated whether activation within the amygdala, a brain region closely linked to the processing of threat, may also function as a predictor of RTs, similar to trait anxiety scores. After threat conditioning by means of aversive electric shocks, 45 participants performed a choice RT task during alternating 30 s blocks in the presence of the threat conditioned stimulus [CS+] or of the safe control stimulus [CS-]. Trait anxiety was assessed with the State-Trait Anxiety Inventory and participants were median split into a high- and a low-anxiety subgroup. We tested three hypotheses: (1) RTs will be faster during the exposure to threat compared to the safe condition in individuals with high trait anxiety. (2) The amygdala fMRI signal will be higher in the threat condition compared to the safe condition. (3) Amygdala fMRI signal prior to a RT trial will be correlated with the corresponding RT. We found that, the high-anxious subgroup showed faster responses in the threat condition compared to the safe condition, while the low-anxious subgroup showed no significant difference in RTs in the threat condition compared to the safe condition. Though the fMRI analysis did not reveal an effect of condition on amygdala activity, we found a trial-by-trial correlation between blood-oxygen-level-dependent signal within the right amygdala prior to the CRT task and the subsequent RT. Taken together, the results of this study showed that exposure to threat modulates task performance. This modulation is influenced by personality trait. Additionally and most importantly, activation in the amygdala predicts behavior in a simple task that is performed during the exposure to threat. This finding is in line with “attentional capture by threat”—a model that includes the amygdala as a key brain region for the process that causes the response slowing.
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32

Eccles, Lee H. "PRESSURE BELT FOR WING LOADS MEASUREMENT." International Foundation for Telemetering, 2001. http://hdl.handle.net/10150/606396.

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International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Boeing Commercial Airplanes has used many methods in the past to measure the structural loads on the wings of its airplanes. The most recent approach is to use arrays of MEMS pressure sensors on the top and bottom surfaces of the wings. By knowing the difference in pressure between the top and bottom of the wings the structural loads on the wings can be calculated. It was decided that in order to build an array of 1100 sensors it would be necessary to condition the sensors and convert the analog output to a digital form at the site of the pressure measurement. This process was taken one step further by converting the output of the A/D converter into engineering units within the sensor module as well. The array is built using a flex circuit card in one foot sections that can be interconnected to form an array of up to 125 sensors. There is a sensor location every two inches on the flex circuit but not all locations are populated. This paper will describe not only the pressure belt but the lessons learned during the development and the implications that these lessons have for smart transducers in general.
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33

Riedel, Philipp, Mark J. Jacob, Dirk K. Müller, Nora C. Vetter, Michael N. Smolka, and Michael Marxen. "Amygdala fMRI Signal as a Predictor of Reaction Time." Frontiers Research Foundation, 2016. https://tud.qucosa.de/id/qucosa%3A29972.

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Reaction times (RTs) are a valuable measure for assessing cognitive processes. However, RTs are susceptible to confounds and therefore variable. Exposure to threat, for example, speeds up or slows down responses. Distinct task types to some extent account for differential effects of threat on RTs. But also do inter-individual differences like trait anxiety. In this functional magnetic resonance imaging (fMRI) study, we investigated whether activation within the amygdala, a brain region closely linked to the processing of threat, may also function as a predictor of RTs, similar to trait anxiety scores. After threat conditioning by means of aversive electric shocks, 45 participants performed a choice RT task during alternating 30 s blocks in the presence of the threat conditioned stimulus [CS+] or of the safe control stimulus [CS-]. Trait anxiety was assessed with the State-Trait Anxiety Inventory and participants were median split into a high- and a low-anxiety subgroup. We tested three hypotheses: (1) RTs will be faster during the exposure to threat compared to the safe condition in individuals with high trait anxiety. (2) The amygdala fMRI signal will be higher in the threat condition compared to the safe condition. (3) Amygdala fMRI signal prior to a RT trial will be correlated with the corresponding RT. We found that, the high-anxious subgroup showed faster responses in the threat condition compared to the safe condition, while the low-anxious subgroup showed no significant difference in RTs in the threat condition compared to the safe condition. Though the fMRI analysis did not reveal an effect of condition on amygdala activity, we found a trial-by-trial correlation between blood-oxygen-level-dependent signal within the right amygdala prior to the CRT task and the subsequent RT. Taken together, the results of this study showed that exposure to threat modulates task performance. This modulation is influenced by personality trait. Additionally and most importantly, activation in the amygdala predicts behavior in a simple task that is performed during the exposure to threat. This finding is in line with “attentional capture by threat”—a model that includes the amygdala as a key brain region for the process that causes the response slowing.
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34

Paredes, Daniel A. "The role of norepinephrine in learning : cerebellar motor learning in rats." [Tampa, Fla] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0001922.

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35

Holmström, Johnny. "GOVERNOR ELECTRONICS FOR DIESEL ENGINES : High availability platform for real-time control and advanced fuel efficiency algorithms." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-20282.

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Fossil fuel is a rare commodity and the combustion of this fuel results in negative environmental effects. This paper evaluates and validates the electronics needed to run intelligent algorithms to lower the fuel consumption for commercial vessels. This is done by integrating advanced fuel saving functions into an electronic device that controls the fuel injection of large diesel engines, as known as a diesel engine governor. The control system is classified as a safety critical system. This means that the electronics needs to be designed for fail safe operation. To allow for future research and development, the platform needs flexibility in respect to hardware reconfiguration and software changes, i.e. this is the basis for a system that allows for hardware-software co-design. For efficient installation and easy commissioning, the system shall allow for auto-calibration combined with programmable jumper selections to attain a cost effective solution. The computation of the fuel saving algorithm require accurate data to build a model of the vessels motions. This is achieved by integrating state of the art sensors and a multitude of communication interfaces. Among other things gyroscopes contra accelerometers where evaluated to find the best solution in respect to cost and performance. This design replace the current product DEGO III. The new product requires the same functionality and shall allow for more functions. Focus has been spent on communication, methods of accruing sensor data and more computation speed. In creating a new generation of a product there are tasks like selecting components, questions pertaining to layout of the printed circuit board and an evaluation of supply chains. The manufacturing aspects are considered to rationalize production and testing.
Fossila bränslen är en dyrbar råvara och förbränningen av detta bränsle leder till negativa miljöeffekter. Detta papper utvärderar och verifierar elektroniken som behövs för att beräkna intelligenta algoritmer som minskar bränsle konsumtionen för kommersiella fartyg. Detta görs genom att sammanfoga avancerade funktioner i en och samma elektroniska enhet som kontrollerar bränsle insprutningen på stora diesel motorer, denna elektronik är känd som en varvtals regulator. Kontroll systemet är klassificerat som ett säkerhetskritiskt system. Detta betyder att elektroniken måste utformas för att vara felsäker. För att tillåta framtida forskning och utveckling behöver plattformen vara flexibel. Den ska tillåta konfiguration av hårdvara och mjukvara ändringar. Samverkan mellan hårdvara och mjukvara. För effektiv installation samt drifttagning, måste systemet vara automat-kalibrerande och utrustat med programmerbara byglingar som möjliggör en kostnadseffektiv lösning. Beräkningen av bränsle optimeringen behöver en detaljerad modell av fartygets rörelse. Detta möjliggörs genom att integrera moderna sensorer och en mängd olika kommunikationsmedier. Bland annat så utvärderades gyroskop kontra accelerometrar för att hitta den bästa lösningen i förhållande till kostnad och kvalitet. Denna design ersätter den nuvarande produkten DEGO III. Den nya produkten behöver samma funktionalitet samt en mängd nya funktioner. Fokus har varit kommunikation, metoder för att samla sensordata och ökad beräknings kraft. När en ny generation av en produkt ska utvecklas finns uppgifter så som att välja komponenter, frågor gällande mönsterkorts layout och en utvärdering av leverantörs källor. Tillverkningen av prototypen inkluderar utvärdering av produktions metoder för att effektivisera tillverkning och verifiering.
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36

Troth, Bill. "TRADEOFFS TO CONSIDER WHEN SELECTING AN AIRBORNE DATA ACQUISITION SYSTEM." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/606787.

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International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California
Selecting an airborne data acquisition system involves compromises. No single data acquisition system can be at the same time, lowest cost, smallest, easiest to use and most accurate. The only way to come to a reasonable decision is to carefully plan the project, taking into account what measurements will be required, what are the physical environments involved, what personnel and resources will be needed and of course, how much money is available in the budget? Getting the right mix of equipment, resources and people to do the job within the schedule and the budget is going to involve a number of tradeoffs. A good plan and a thorough knowledge of available resources and equipment will allow you make the necessary decisions. Hopefully, this paper will offer some suggestions that will aid in preparing your plan and give some insight into available system alternatives.
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37

Kim, Woochan. "Integrated Current Sensor using Giant Magneto Resistive (GMR) Field Detector for Planar Power Module." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/46064.

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Conventional wire bond power modules have limited application for high-current operation, mainly because of their poor thermal management capability. Planar power modules have excellent thermal management capability and lower parasitic inductance, which means that the planar packaging method is desirable for high-power applications. For these reasons, a planar power module for an automotive motor drive system was developed, and a gate-driver circuit with an over-current protection was planned to integrate into the module. This thesis discusses a current-sensing method for the planar module, and the integrated gate driver circuit with an over-current protection. After reviewing several current-sensing methods, it becomes clear that most popular current-sensing methods, such as the Hall-Effect sensor, the current transformer, the Shunt resistor, and Rogowski coils, exhibit limitations for the planar module integration. For these reasons, a giant magneto resistive (GMR) magnetic-field detector was chosen as a current-sensing method. The GMR sensor utilizes the characteristics of the giant magneto resistive (GMR) effect in that it changes its resistance when it is exposed to the magnetic-flux. Because the GMR resistor can be fabricated at the wafer level, a packaged GMR sensor is very compact when compared with conventional current sensors. In addition, the sensor detects magnetic-fields, which does not require direct contact to the current-carrying conductor, and the bandwidth of the sensor can be up to 1 MHz, which is wide enough for the switching frequencies of most of motor drive applications. However, there are some limiting factors that need to be considered for accurate current measurement: â ¢ Operating temperature â ¢ Magnetic-flux density seen by a GMR resistor â ¢ Measurement noise If the GMR sensor is integrated into the power module, the ambient temperature of the sensor will be highly influenced by the junction temperature of the power devices. Having a consistent measurement for varying temperature is important for module-integrated current sensors. An experiment was performed to see the temperature characteristics of a GMR sensor. The measurement error caused by temperature variation was quantified by measurement conditions. This thesis also proposes an active temperature error compensation method for the best use of the GMR sensor. The wide current trace of the planar power module helps to reduce the electrical/thermal resistance, but it hinders having a strong and constant magnetic-field-density seen by the GMR sensor. In addition, the eddy-current effect will change the distribution of the current density and the magnetic-flux-density. These changes directly influence the accurate measurement of the GMR sensor. Therefore, analyzing the magnetic-flux distribution in the planar power module is critical for integrating the GMR sensor. A GMR sensor is very sensitive to noise, especially when it is sensing current flowing in a wide trace and exposed to external fields, neither of which can be avoided for the operation of power modules. Post-signal processing is required, and the signal-conditioning circuit was designed to attenuate noise. The signal-conditioning circuit was designed using an instrumentation amplifier, and the circuit attenuated most of the noise that hindered accurate measurement. The over-current protection circuit along with the gate driver circuit was designed, and the concept was verified by experiments. The main achievements of this study can be summarized as: â ¢ Characterization of conventional current-sensing methods â ¢ Temperature characterization of the GMR resistor â ¢ Magnetic-flux distribution of the planar power module â ¢ Design of the signal-conditioning circuit and over-current protection circuit
Master of Science
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38

Powell, Rick, and Chris Fitzsimmons. "INTELLIGENT DATA ACQUISITION TECHNOLOGY." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607551.

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International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada
Telemetry & Instrumentation, in conjunction with NASA’s Kennedy Space Center, has developed a commercial, intelligent, data acquisition module that performs all functions associated with acquiring and digitizing a transducer measurement. These functions include transducer excitation, signal gain and anti-aliasing filtering, A/D conversion, linearization and digital filtering, and sample rate decimation. The functions are programmable and are set up from information stored in a local Transducer Electronic Data Sheet (TEDS). In addition, the module performs continuous self-calibration and self-test to maintain 0.01% accuracy over its entire operating temperature range for periods of one year without manual recalibration. The module operates in conjunction with a VME-based data acquisition system.
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39

D'Anniballe, Riccardo. "Sviluppo e caratterizzazione elettromeccanica di un sensore piezoelettrico nanofibroso per applicazioni in laminati compositi." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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Nell’elaborato di tesi magistrale, dal titolo “Sviluppo e caratterizzazione elettromeccanica di un sensore piezoelettrico nanofibroso per applicazioni in laminati compositi”, si è studiata la possibilità di produrre un laminato composito sensorizzato con finalità di Structural Health Monitoring (SHM). Lo studio si è concentrato sui materiali piezoelettrici che risultano particolarmente adatti per finalità di sensing in quanto rispondono ad uno stimolo meccanico con una variazione nel livello di polarizzazione elettrica. Nel lavoro di tesi è descritto il processo produttivo in tutte le sue fasi per la realizzazione di un sensore piezoelettrico che ricalchi la struttura del GLARE (Glass Reinforced Aluminium Laminate). Si tratta di un laminato avanzato per applicazioni aerospaziali strutturali costituito da fogli di alluminio intervallati da strati di pre-preg in fibra di vetro (GFRP-Glass Fiber Reinforced Polymers). La sensorizzazione è stata ottenuta attraverso l’utilizzo di nanofibre piezoelettriche di P(VDF-TrFE), realizzate tramite la tecnica dell’elettrofilatura, e integrate nel laminato, permettendo un monitoraggio costante di tutta la struttura. Obiettivo principale della tesi è stato quello di realizzare un modello matematico-circuitale equivalente del sensore, in grado di prevedere la risposta del sensore per qualsiasi tipologia di forza in ingresso. In particolare, si è sviluppato uno studio sull’effetto della variazione dei parametri circuitali del sistema di acquisizione, che in alcune condizioni permette di rilevare carichi quasi-statici, nonostante il sensore piezoelettrico sia adatto principalmente alla rilevazione di carichi dinamici
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40

Lima, Alison Lins de. "Desenvolvimento de um sistema para aquisição e processamento de sinais utilizando a plataforma TivaWareTM para aplicações em Smart Grid." Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/7633.

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Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2015-11-24T11:18:29Z No. of bitstreams: 1 arquivototal.pdf: 5459157 bytes, checksum: e363929cf9a6a71b88515b8a24c12af6 (MD5)
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Amid a scenario, that contrasts the increasing demand for electricity, and decreased ability to generation from conventional sources, which is creating serious problems for the energy sector, the concept of smart grids popularizes up and presented as an alternative to, among other possibilities, minimize the effects of power outages in the design of distributed generation from alternative sources. In order for alternatives to that end, it will develop a data acquisition system, low cost and high performance for applications in smart grids, which facilitates monitoring of electricity in real time, where the user can manage their own control avoiding waste and consequently saving. The system will be developed based on the standards of ANEEL (Brazilian Electricity Regulatory Agency), body responsible for determining the minimum parameters a measuring equipment must possess. The data acquisition system showed results with a high degree of agreement when compared with the reference instrument, the fluke 434/435. A response curve of voltage and current, showing the system behavior compared to other instruments of measurement was introduced. Still, it is objective of the work that the signs Conditioning Unit can be adapted for multiple microprocessor platforms, using simple settings, without the need for hardware reconfiguration. This fact has been proven to be used with Black BeagleBone with satisfactory results.
Em meio a um cenário que contrasta o aumento da demanda por energia elétrica, e a diminuição da capacidade de geração a partir das fontes convencionais, o que vem gerando sérios problemas para o setor energético, o conceito de smart grids populariza-se e apresenta-se como uma alternativa para, entre outras possibilidades, minimizar os efeitos da falta de energia elétrica, na concepção de geração distribuída a partir de fontes alternativas. Com vistas em alternativas com esse fim, será desenvolvido um sistema de aquisição de dados, de baixo custo e alto desempenho, para aplicações em smart grids, que viabilize o monitoramento da energia elétrica em tempo real, onde o usuário possa gerir o seu próprio controle evitando o desperdício e, consequentemente, economizando. O sistema será desenvolvido com base nas normas da ANEEL (Agência Nacional de Energia Elétrica), órgão responsável por determinar os parâmetros mínimos que um equipamento de medição deve possuir. O sistema de aquisição de dados apresentou resultados com alto grau de concordância ao ser comparados com o instrumento de referência, o fluke 434/435. Foi apresentado uma curva resposta da tensão e corrente, mostrando o comportamento do sistema em comparação a de outros instrumentos de medições. Ainda, é objetivo do trabalho que a Unidade de Condicionamento dos Sinais, possa ser adaptada para múltiplas plataformas microprocessadas, através de simples ajustes, sem a necessidade de reconfiguração de hardware. Esse fato foi comprovado ao ser utilizada com a BeagleBone Black, apresentando resultados satisfatórios.
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41

Burke, Christopher J. "Layered Reward Signalling Through Octopamine and Dopamine in Drosophila: A Dissertation." eScholarship@UMMS, 2013. http://escholarship.umassmed.edu/gsbs_diss/657.

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Evaluating our environment by deciding what is beneficial or harmful, pleasant or punishing is a part of our daily lives. Seeking pleasure and avoiding pain is a common trait all mobile organisms exhibit and understanding how rewarding stimuli are represented in the brain remains a major goal of neuroscience. Studying reward learning in the fruit fly, Drosophila melanogaster has enabled us to better understand the complex neural circuit mechanisms involved in reward processing in the brain. By conditioning flies with sugars of differing nutritional properties, we determined that flies trained with sweet but non-nutritive sugars formed robust short-term memory (STM), but not long-term memory (LTM). However, flies conditioned with a sweet and nutritious sugar or a sweet non-nutritious sugar supplemented with a tasteless nutritious compound, formed robust 24 hour LTM. These findings led us to propose a model of parallel reinforcement pathways for appetitive olfactory conditioning in the fly, in which both sweet taste and nutrient value contribute to appetitive long-term memory. We followed this line of research by examining the neural circuitry in the fly brain that represents these parallel reward pathways. We found that the biogenic amine octopamine (OA) only represents the reinforcing effects of sweet taste. Stimulation of OA neurons could replace sugar in olfactory conditioning to form appetitive STM. Surprisingly, implanting memory with OA was dependent on dopamine (DA) signaling, which although being long associated with reward in mammals, was previously linked with punishment in flies. We found that OA-reinforced memory functions through the α-adrenergic OAMB receptor in a novel subset of rewarding DA neurons that innervate the mushroom body (MB). The rewarding population of DA neurons is required for sweet and nutrient reinforced memory suggesting they may integrate both signals to drive appetitive LTM formation. In addition, OA implanted memory requires concurrent modulation of negatively reinforcing DA neurons through the β-adrenergic OCTβ2R receptor. These data provide a new layered reward model in Drosophila in which OA modulates distinct populations of both positive and negative coding DA neurons. Therefore, the reinforcement system in flies is more similar to that of mammals than previously thought.
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42

Kammara, Subramanyam Abhaya Chandra [Verfasser], and Andreas [Akademischer Betreuer] König. "Conception and First Implementation of Novel Sensory Signal Conditioning and Digital Conversion Electronics Based on Spiking Neuron Ensembles for Inherently Robust Processing in Aggressively Scaled Integration Technologies / Abhaya Chandra Kammara Subramanyam ; Betreuer: Andreas König." Kaiserslautern : Technische Universität Kaiserslautern, 2017. http://d-nb.info/1138630594/34.

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43

Oliveira, Alex Venancio de. "Projeto e desenvolvimento de um condicionador de sinais com saida 4-20mA com isolamento optico." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259315.

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Orientador: Jose Antonio Siqueira Dias
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: O presente trabalho tem por objetivo o projeto, desenvolvimento e montagem de um Condicionador de Sinais de baixo custo, versátil e com recursos básicos comparáveis aos equipamentos semelhantes existentes no mercado nacional, que são na sua grande maioria importados. O equipamento faz a conversão, filtragem, isolação e condicionamento de pequenos sinais de controle provenientes de diversos tipos de sensores e transdutores, comuns em ambiente industrial, utilizando uma tecnologia bem consolidada de transporte de sinais em malhas de controle industriais: o transporte no modo corrente de 4-20mA. Esta tecnologia, mesmo frente à novos desenvolvimentos digitais na área de controle e transmissão de sinais em ambiente industrial, resiste como alternativa econômica e de ótimos resultados, mesmo em ambientes extremamente agressivos, com altos níveis de interferência
Abstract: In this work it is presented the design, development and implementation of a low cost and versatile signal conditioner which is similar to the products available in the Brazilian market, most of them imported. The developed equipment performs the conversion, filtering, isolation and conditioning of small control signals from various types of sensors and transducers commonly used in industrial environments, by using a mature technology of signal transport in industrial control loops: current mode of 4-20mA. This technology, despite of new digital developments in the area of control and signal transmission in industrial environments, resists as an economic alternative with excellent results, especially in extremely aggressive environments with high levels of interference
Mestrado
Eletrônica, Microeletrônica e Optoeletrônica
Mestre em Engenharia Elétrica
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44

Abboud, Dany. "Vibration-based condition monitoring of rotating machines in nonstationary regime." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0106/document.

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Dans les dernières décennies, la surveillance vibratoire des machines tournantes a acquis un intérêt particulier fournissant une aide efficace pour la maintenance dans l'industrie. Aujourd'hui, de nombreuses techniques efficaces sont bien établies, ancrées sur des outils puissants offerts notamment par la théorie des processus cyclostationnaires. Cependant, toutes ces techniques reposent sur l'hypothèse d’un régime de fonctionnement (c.à.d. vitesse et/ou charge) constant ou éventuellement fluctuant d’une façon stationnaire. Malheureusement, la plupart des machines surveillées dans l'industrie opèrent sous des régimes non stationnaires afin de remplir les tâches pour lesquelles elles ont été conçues. Dans ce cas, ces techniques ne parviennent pas à analyser les signaux vibratoires produits. Ce problème a occupé la communauté scientifique dans la dernière décennie et des techniques sophistiquées de traitement du signal ont été conçues pour faire face à la variabilité du régime. Mais ces tentatives restent limitées, dispersées et généralement peu soutenues par un cadre théorique. Le principal objectif de cette thèse est de combler partiellement cette lacune sur la base d'une formalisation théorique du sujet et d’un développement systématique de nouveaux outils de traitement du signal. Dans ce travail, la non-stationnarité du régime est limitée à celle de la vitesse— c.à.d. vitesse variable et charge constante— supposée connue a priori. Afin d'atteindre cet objectif, la méthodologie adoptée consiste à étendre le cadre cyclostationnaire avec ses outils dédiés. Nous avons élaboré cette stratégie en distinguant deux types de signatures. Le premier type comprend des signaux déterministes connus comme cyclostationnaires au premier ordre. La solution proposée consiste à généraliser la classe cyclostationnaire au premier ordre à la classe cyclo-non-stationnaire au premier ordre qui comprend des signaux déterministes en vitesse variable. Le second type comprend des signaux aléatoires périodiquement corrélés connus comme cyclostationnaires au deuxième ordre. Trois visions différentes mais complémentaires ont été proposées pour traiter les variations induites par la non-stationnarité de la vitesse de fonctionnement. La première adopte une approche cyclostationnaire angle\temps, la seconde une solution basée sur l'enveloppe et la troisième une approche cyclo-non-stationnaire (au second ordre). De nombreux outils ont été conçus dont les performances ont été testées avec succès sur des signaux vibratoires réels et simulés
In the last decades, vibration-based condition monitoring of rotating machine has gained special interest providing an efficient aid for maintenance in the industry. Nowadays, many efficient techniques are well-established, rooted on powerful tools offered in particular by the theory of cyclostationary processes. However, all these techniques rely on the assump-tion of constant— or possibly fluctuating but stationary— operating regime (i.e. speed and/or load). Unfortunately, most monitored machines used in the industry operate under nonstationary regimes in order to fulfill the task for which they have been designed. In this case, these techniques fail in analyzing the produced vibration signals. This issue, therefore, has occupied the scientific committee in the last decade and some sophisticated signal processing techniques have been conceived to deal with regime variability. But these works remain limited, dispersed and generally not supported by theoretical frameworks. The principal goal of this thesis is to partially fill in this gap on the basis of a theoretical formalization of the subject and a systematic development of new dedicated signal processing tools. In this work, the nonstationarity of the regime is confined to that of the speed— i.e. variable speed and constant load, assumed to be known a priori. In order to reach this goal, the adopted methodology consists in extending the cyclostationary framework together with its dedicated tools. We have elaborated this strategy by distinguishing two types of signatures. The first type includes deterministic waveforms known as first-order cyclostationary. The proposed solution consists in generalizing the first-order cyclostationary class to the more general first-order cyclo-non-stationary class which enfolds speed-varying deterministic signals. The second type includes random periodically-correlated waveforms known as second-order cyclostationary. Three different but complementary visions have been proposed to deal with the changes induced by the nonstationarity of the operating speed. The first one adopts an angle\time cyclostationary approach, the second one adopts an envelope-based solution and the third one adopts a (second-order) cyclo-non-stationary approach. Many tools have been conceived whose performances have been successfully tested on simulated and real vibration signals
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45

Nguyen, Tuan Ngoc. "An algorithm for extracting the PPG Baseline Drift in real-time." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2016. https://ro.ecu.edu.au/theses/1801.

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Photoplethysmography is an optical technique for measuring the perfusion of blood in skin and tissue arterial vessels. Due to its simplicity, accessibility and abundance of information on an individual’s cardiovascular system, it has been a pervasive topic of research within recent years. With these benefits however there are many challenges concerning the processing and conditioning of the signal in order to allow information to be extracted. One such challenge is removing the baseline drift of the signal, which is caused by respiratory rate, muscle tremor and physiological changes within the body as a response to various stimuli. Over the years there have been many methods developed in order to condition the signal such as Wavelet Transform, Cubic Spline Interpolation, Morphological Operators and Fourier-Based filtering techniques. All have their own individual benefits and drawbacks. These drawbacks are that they are unsuitable for real-time usage due to the computation power needed, or have the trade-off of being real-time at the cost of deforming the signal which is unideal for accurate analysis. This thesis aims to explore these techniques in order to develop an algorithm that can be used to condition the signal against the baseline drift in real-time, while being able to achieve good computational efficiency and the preservation of the signal form.
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46

Ibarra, Alejandro Rafael Garcia. "Desenvolvimento de transmissores de pressão diferencial baseados em sensores piezoresistivos e saída analógica de 4-20 mA." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-19032015-163304/.

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Este projeto de pesquisa apresenta o desenvolvimento de protótipos de transmissores industriais de pressão do tipo diferencial piezoresistivo com saída analógica a dois fios 4-20 mA. Os dispositivos usam um DSSP (processador digital de sinal do sensor) para realizar compensação térmica nas temperaturas de 0°C até 80°C e a calibração de pressão diferencial na faixa de 0-25 bard e de pressão de linha de 0-7 barg. Os transmissores permitem a leitura de diversas variáveis industriais: pressão diferencial, pressão relativa e pressão absoluta em fluidos. Os transmissores têm um TEB (total error band) menor que 0,15 de porcentagem de escala plena. A saída analógica dos transmissores diferenciais de pressão é caracterizada utilizando como base normas internacionais BS (British Standards). Os parâmetros avaliados nos transmissores de pressão são: a exatidão, o coeficiente térmico do offset, o coeficiente térmico do span, o total error band, e os desvios no tempo a curto e longo prazo. Esse trabalho é resultado da parceria dada entre o Laboratório de Sistemas Integráveis da Escola Politécnica da Universidade de São Paulo (LSI/EPUSP) e a empresa MEMS Microssistemas Integrados Híbridos de Pressão.
This research project presents the prototypes development of piezoresistive differential pressure transmitters with analog two-wire output of 4-20 mA. The devices use a DSSP (Digital Signal Processor Sensor) to achieve temperature compensation at temperatures from 0°C to 80°C and differential pressure calibration range from 0 bard to 25 bard and line pressure range from 0 barg to 7 barg. The transmitters measure several industrial variables: differential pressure, relative pressure and absolute pressure at fluids. The transmitters have a TEB (total error band) less than 0.15 percent of full scale. The analog output of the differential pressure transmitters is characterized using British Standards-BS. The parameters evaluated in the pressure transmitters are: the accuracy, the thermal coefficient of the offset, the thermal coefficient of the span, the total error band, the start-up drift and long-term drift. This work is the result of the academic and technological partnership between the Laboratory of Integrated Systems of the Polytechnic School of the University of São Paulo (LSI / EPUSP) and the MEMS company - Microssistemas Integrados Híbridos de Pressão Ltda.
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47

Šantavý, Marek. "Univerzální měřící ústředna." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236523.

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The aim of this thesis is to create data acquisition application. The software module is designed for the industrial panel PC. Power Panel 520 from Bernecker + Reiner and the data acquisition board NI USB-6215 from National Instruments represent the fundamental hardware components for this project. Data acquisition and visualization tasks are controlled by a standalone application made in LabVIEW 2011. OPC, industrial standard in communication, is responsible for mutual interconnection between control (PLC) and data acquisition part. Network shared variables and Apple iPad 2 allow remote surveillance for operator. Finally, the creation of user-friendly interface and integration of technologies from different vendors, are main goals of this project.
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48

Marques, Gustavo Pires 1978. "Análise do potencial de calibração da força óptica através de dispositivos de microscopia de força atômica." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277492.

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Orientador: Carlos Lenz Cesar
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
Made available in DSpace on 2018-08-20T14:50:59Z (GMT). No. of bitstreams: 1 Marques_GustavoPires_M.pdf: 1771357 bytes, checksum: 8ee6919633e2615608f25b33bec98e96 (MD5) Previous issue date: 2005
Resumo: O microscópio de força atômica é uma ferramenta que possibilita a medida de forças precisamente localizadas com resoluções no tempo, espaço e força jamais vistas. No coração deste instrumento está um sensor a base de uma viga (cantilever) que é responsável pelas características fundamentais do AFM. O objetivo desta pesquisa foi usar a deflexão deste cantilever para obter uma calibração rápida e precisa da força da armadilha da pinça óptica, assim como testar e comparar com os método tradicionalmente utilizados para este propósito. Para isso, foi necessário analisar e entender o condicionamento de sinais utilizados no AFM. Foram estudados cantilever tradicionais, cujo sistema de detecção é baseado na deflexão de um feixe laser em conjunto com fotodetectores, bem como cantilevers piezoresistivos. Cantilevers piezoresistivos fornecem uma alternativa simples e conveniente aos cantilevers ópticos. A integração de um elemento sensorial dentro do cantilever elimina a necessidade de um laser externo e de um detector utilizados na maioria dos AFMs. Isto elimina a etapa delicada de alinhamento da laser ao cantilever e fotodetector que normalmente precede uma medida com AFM, uma simplificação que expande o potencial do AFM para o uso em meios adversos, como câmaras de ultra alto vácuo ou, como no caso específico das Pinças Ópticas, onde existem esferas em solução líquida e também restrições de dimensão
Abstract: The atomic force microscope (AFM) is a tool that enables the measurement of precisely localized forces with unprecedented resolution in time, space and force. At the heart of this instrument is a cantilever probe that sets the fundamental features of the AFM. The objective of this research has been using the deflection of this cantilever to get a fast and accurate calibration of optical tweezers trap force, as well as testing and comparing to the traditionally used methods of calibration for this purpose. For that it was necessary to resolve and understand the sensors signals conditioning used in the AFM. Traditional cantilevers, whose detection system is based on the deflection of a laser beam in addition with a photodetector, as well as piezoresistive cantilevers has been studied. Piezoresistive cantilevers provide a simple and convenient alternative to optically detected cantilevers. Integration of a sensing element into the cantilever eliminates the need for the external laser and detector used in most AFMs. This removes the delicate step of aligning the laser to the cantilever and photodetector which usually precedes an AFM measurement, a simplification which expands the potential of the AFM for use in difficult environments such as ultrahigh vacuum chambers or, as in Optical Tweezers specific case, where there are spheres into a liquid solution as well as dimensional constraints
Mestrado
Física
Mestre em Física
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49

Guigue, Lisa. "Evaluation clinique de la pression artérielle centrale à partir de la mesure par cathétérisme radial en utilisant la modélisation de l'arbre artériel, de la liaison hydraulique et du capteur. Intégration de la fonction dans un dispositif de surveillance de la qualité de la mesure de la pression artérielle." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAS036.

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La pression centrale est le reflet de l'état hémodynamique du patient et son estimation se fait par l'acquisition de la pression artérielle radiale plus facilement accessible chez la majorité des patients en anesthésie-réanimation et soins intensifs. Cette thèse tente de résoudre les difficultés de l’évaluation de la pression centrale à partir du cathétérisme radial associé à un capteur de pression via une liaison hydraulique. Ces freins à l'évaluation sont :1.les altérations liées à la liaison hydraulique entre le cathéter radial et le capteur;2.les distorsions liées à l’arbre artériel entre le cœur et la périphérie (artère radiale). Il existe des cas cliniques où les propriétés de l’arbre artériel sont modifiées de telle sorte que la pression périphérique n’est plus le reflet de la pression centrale et donc ne peut plus l'estimer correctement. L'un de ces phénomènes est connu sous le terme de découplage entre pressions artérielles centrale et périphérique.Pour la première difficulté, le dispositif médical CAThétérisme Artériel Radial en Soins Intensifs (CATARSI) développé par AII Biomédical apporte une solution à ce problème en fournissant un indice de la qualité de la mesure par cathéter et liaison hydraulique.Dans les cas physiopathologiques entraînant une mauvaise estimation de la PA central, la possibilité d’alerter le personnel soignant sur l’apparition de ces situations serait optimale. Cette fonction pourrait être intégrée au dispositif CATARSI. Au préalable, il faut comprendre, évaluer et modéliser de manière précoce, les mécanismes mis en jeu dans ces situations cliniques particulières.Le travail de thèse s'articule donc selon 3 axes :1.Evaluation expérimentale, par oscillométrie et cathétérisme, de la mesure de la vitesse de propagation de l’onde de pouls le long de l’arbre artériel chez l’homme (Pression artérielle centrale, radiale, fémorale) en situation de découplage entre pression centrale/pression périphérique. Cette évaluation sera faite chez des patients en CEC (Circulation Extra-Corporelle) car ils peuvent présenter des découplages. Plusieurs phases de mesures sont prévues avant, pendant et après la CEC.2.Recherche et optimisation d’une méthode de détection automatique du découplage entre pression artérielle centrale et périphérique à partir de l’analyse du signal de pression radiale en continu et d’une mesure complémentaire effectuée par le clinicien avec un autre capteur sur proposition du dispositif CATARSI.3.Proposition d’un ou plusieurs modèles du segment central-radial de l’arbre artériel afin d’obtenir une meilleure évaluation de la pression artérielle centrale à partir de la mesure de pression radiale par cathéter pour ensuite intégrer de nouvelles fonctionnalités dans le dispositif CATARSI
Aortic pressure is generally recognized as a good index of the hemodynamic state of a patient. In intensive care units, aortic pressure is indirectly estimated via a radial catheter-tansducer system. The present study aims to remove the obstacles to a reliable evaluation of central pressure via the radial catheter-transducer system commonly used in clinics. These obstacles can be due to :1.technical problems occurring between the radial catheter and the sensor;}2.pathophysiological problems affecting the arterial tree between the heart and peripheral arteries. Several clinical situations have been identified in which alterations of the physical properties of the vasculature do not allow a reliable estimation of central arterial pressure using the common radial setting. One of these phenomena is the so called central-to-radial arterial pressure gradient.CATARSI, a medical device developped by AII SAS, affords a solution to the first group of problems by providing an index of the quality of the signal provided by the radial catheter-transducer system.Under pathophysiological conditions affecting the arterial vascualture of the patient, early detection of a mismatch between peripheral and central arterial pressure would also be of great clinical value. In this view, a new functionality could be develop to implement CATARSI. However, to achieve this goal, it is first necessary to understand, evaluate and modelize the precise pathophysiological mechanisms involved in these particular situations.The study contains three steps :1.Experimental evaluation, by oscillometry and catheterization, of AP propagation-time on the human arterial tree (aortic, radial, femoral arterial pressure) during a central-to-radial arterial pressure gradient. This evaluation has been carried out on patients undergoing Cardio Pulmonary Bypass (CPB). Several measurements have been performed: before, during and after CPB.2.Development and optimization of a method allowing the detection of an uncoupling between central and peripheral arterial pressure thanks to AP signal analysis in real time and a potential complementary measurement performed with CATARSI.3.Several central to radial arterial modelling propositions in order to present a better evaluation of central arterial pressure estimated by radial arterial pressure
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50

Yu, Xiaoyang. "Dynamic acoustic emission for the characterization of the nonlinear behavior of complex materials." Thesis, Le Mans, 2020. http://www.theses.fr/2020LEMA1019.

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L’émission acoustique (EA) est reconnue pour être une technique efficace de surveillance de la santé des structures permettant de détecter la création et la propagation de microfissures dans les matériaux structuraux tels que le béton ou les composites lorsqu'ils sont soumis à des contraintes quasi-statiques. Sur la base de méthodes de traitement de signaux adéquates, différentes études ont établi des liens entre les salves d’EA et les micro-dommages créés. D'autres travaux ont montré qu'il est possible de corréler le temps de relaxation des composites et l'énergie des mécanismes d'endommagement mesurée durant la charge quasi-statique en utilisant les salves d’EA enregistrées. Cette thèse propose d'utiliser un protocole expérimental original pour détecter la relaxation non-linéaire d'échantillons de bétons à l'état intact et endommagés. Ce protocole est basé sur l'utilisation de l’EA pour capter passivement la relaxation non-linéaire d'échantillons de bétons au lieu du signal de faible amplitude habituellement utilisé dans les expériences de dynamique lente. Les résultats montrent que les méthodes de détection passives et actives conduisent à des temps de relaxation équivalents. De plus, le capteur d’EA révèle l’existence d’une ‘période de silence’ pendant les premières minutes de la relaxation non-linéaire après laquelle les salves d’EA commencent à être détectées. De plus, les caractéristiques des salves d’EA enregistrées pendant la relaxation passive ont montré une nette ressemblance avec celles obtenues lors de l'endommagement des mêmes échantillons, où des mécanismes de cisaillement et de compression sont impliqués. Enfin, nous notons qu’en plus de l'utilisation d'une approche de reconnaissance des formes non- supervisée pour la classification des salves d’EA, ce travail propose une nouvelle approche de classification des signaux d’EA basé sur l’image de la représentation en ondelettes continue (CWT) et le réseau de neurones convolutifs (CNN). Les résultats liés aux données d’EA dynamiques non-linéaires et quasi-statiques montrent que les deux approches de traitement du signal ont une grande précision de classification, ce qui représente un intérêt certain pour le développement de méthodes d’EA dynamiques en présence de microfissures
Acoustic emission (AE) is well known to be an efficient structural health monitoring technique to detect the creation and propagation of micro-cracks within structural materials such as concrete or composites when submitted to quasi-static stresses. Based on adequate signal processing methods, different research studies have established links between the detected AE hits and the created micro-damages. Other works have shown that it is possible to correlate the relaxation time in composites and the energy of the damage mechanisms measured during the quasi-static loading using the recorded AE hits. This thesis proposes to use an original experimental protocol to probe the nonlinear relaxation of concrete samples at the intact and damaged states. This protocol is based on the use of AE to passively probe the nonlinear relaxation of concrete samples instead of the weak amplitude signal usually used in slow dynamics experiments. Results show that passive and active probing methods lead to equivalent relaxation times. Furthermore, AE probing reveals the existence of a ‘silence period’ during the first minutes of the nonlinear relaxation after which AE hits start to be detected. In addition, the characteristics of AE hits recorded during the passive relaxation showed a clear resemblance to those obtained during the damaging of the same samples, where shear and compression mechanisms are involved. For the clustering of the AE hits, in addition to use of an unsupervised pattern recognition approach to cluster the detected AE hits, this work proposes a novel ‘image- based AE classification’ approach based on continuous wavelet transform (CWT) and convolutional neural network (CNN). Results related to the nonlinear dynamic and quasi-static AE data show that both signal processing approaches have high classification accuracy, which represents a great interest in the development of dynamic AE methods in the presence of micro-cracks
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