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

A MULTIPLEXER/RECORDER ARCHITECTURE FOR USE WITH CONVENTIONAL MEDIA TECHNOLOGY

Berdugo, Albert 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Instrumentation recorders have evolved continuously over the years. Their growth has primarily been driven by technology advancements. The latest recording equipment generally utilizes hard disk, disk array, or solid-state storage technology, which results in greater capacity and performance. Most recorders integrate storage media with multiplexer electronics resulting in a highly efficient yet inflexible and physically large recording system. This paper describes an instrumentation multiplexer/recorder system using an open architecture between the multiplexer and the storage media that allows insertion of conventional recording technologies. This approach provides a generalized solution with enough flexibility and scalability to address the majority of instrumentation recording needs. This system is based on the latest IRIG-106 chapter 10 standard, thus supporting interoperability throughout the flight test community.
12

DESIGN OF A GIGABIT DATA ACQUISITION AND MULTIPLEXER SYSTEM

Berdugo, Albert 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Gigabits and hundreds of megabit communication buses are starting to appear as the avionic buses of choice for new or upgraded airborne systems. This trend presents new challenges for instrumentation engineers in the areas of high speed data multiplexing, data recording, and data transmission of flight safety information. This paper describes the approach currently under development to acquire data from several types of high-speed avionic buses using distributed multiplexer and acquisition units. Additional input data may include PCM, wideband analog data, discrete, real-time video and others. The system is capable of multiplexing and recording all incoming data channels, while at the same time providing data selection down to the parameter level from input channels for transmission of flight safety information. Additionally, an extensive set of data capture trigger/filter/truncation mechanisms are supported.
13

HIGH SPEED ASYNCHRONOUS DATA MULTIPLEXER/ DEMULTIPLEXER FOR HIGH DENSITY DIGITAL RECORDERS

Berdugo, Albert, Small, Martin 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Modern High Density Digital Recorders (HDDR) are ideal devices for the storage of large amounts of digital and/or wideband analog data. Ruggedized versions of these recorders are currently available and are supporting many military and commercial flight test applications. However, in certain cases, the storage format becomes very critical, e.g., when a large number of data types are involved, or when channel-to-channel correlation is critical, or when the original data source must be accurately recreated during post mission analysis. A properly designed storage format will not only preserve data quality, but will yield the maximum storage capacity and record time for any given recorder family or data type. This paper describes a multiplex/demultiplex technique that formats multiple high speed data sources into a single, common format for recording. The method is compatible with many popular commercial recorder standards such as DCRsi, VLDS, and DLT. Types of input data typically include PCM, wideband analog data, video, aircraft data buses, avionics, voice, time code, and many others. The described method preserves tight data correlation with minimal data overhead. The described technique supports full reconstruction of the original input signals during data playback. Output data correlation across channels is preserved for all types of data inputs. Simultaneous real-time data recording and reconstruction are also supported.
14

Experimental and Finite Element Analysis of Wind Induced Displacement of a Dual Axis Photovoltaic Solar Trackers

Adeleke, Bukola January 2016 (has links)
Photovoltaic (PV) solar panels and trackers represent one of the most common renewable energy technology which converts sunlight radiation into electrical energy. The solar trackers specifically are more complex structures because they involve mechanical devices, a supporting slender structure, and photovoltaic modules mounted and positioned on top of the supporting structure. Solar trackers are mounted on mobile supports or racks, in order to enable the rotation and tilt of the PV which thus maintains their optimum exposure to the incident sunlight. Solar trackers support structures should be designed for wind resistance during the operation and at stow position for its life span and this became a concern considering the new tendency of installing the solar trackers on the rooftop of low-rise or medium-rise buildings. The current research focused on performing site measurements of the wind-induced displacement for a dual-axis solar tracking system installed on the roof of the Mann Parking building of the University of Ottawa, for different azimuth, elevations. The supporting structure of the solar tracker was instrumented with 16 strain gauges and the strains developed in the metal truss members were measured during the months February 2015 and March 2015. The tracker was rotated and tilted at different angles through the duration of the experiment and the strains observed on each structural element were recorded. In order to estimate deflections of the supporting structure for wind speeds higher than the ones measured, a finite element (FE) model of the solar tracker was created and static analysis was performed for different inclinations using the SAP 2000 structural software. The experimental results were in agreement with the FE simulation results as the stresses obtained ranged between 1.02 × 107 Pa and 7.88 × 107 Pa. Lower attack angles between 45° and 60° were found to have significant effect on the elements of the solar tracker irrespective of the wind load magnitude. Operational attack angles between 65° and 75° were found to be safer positions as obtained displacements and stress analysis result showed that the supporting structure of the solar tracker was stable for wind speeds between 0 m/s and 33m/s in Ottawa region
15

New Concepts in Front End Design for Receivers with Large, Multiband Tuning Ranges

Hasan, S. M. Shajedul 30 April 2009 (has links)
This dissertation presents new concepts in front end design for receivers with large, multiband tuning ranges. Such receivers are required to support large bandwidths (up to 10's of MHz) over very large tuning ranges (30:1 and beyond) with antennas that are usually narrowband, or which at best support multiple narrow bandwidths. Traditional techniques to integrate a single antenna with such receivers are limited in their ability to handle simultaneous channels distributed over very large tuning ranges, which is important for frequency-agile cognitive radio, surveillance, and other applications requiring wideband or multiband monitoring. Direct conversion architecture is gaining popularity due to the recent advancements in CMOS--based RFIC technology. The possibility of multiple parallel transceivers in RF CMOS suggests an approach to antenna--receiver integration using multiplexers. This dissertation describes an improved use of multiplexers to integrate antennas to receivers. First, the notion of sensitivity--constrained design is considered. In this approach, the goal is first to achieve sensitivity which is nominally dominated by external (environmental) noise, and then secondly to improve bandwidth to the maximum possible consistent with this goal. Next, a procedure is developed for designing antenna-multiplexer-preamplifier assemblies using this philosophy. It is shown that the approach can significantly increase the usable bandwidth and number of bands that can be supported by a single, traditional antenna. This performance is verified through field experiments. A prototype multiband multimode radio for public safety applications using these concepts is designed and demonstrated. / Ph. D.
16

FIFO-kostruktion baserat på ett enkel-ports SRAM / FIFO-construction based on a single-port SRAM

Duman, Yusuf January 2003 (has links)
<p>Vid implementeringar av FIFO-arkitekturer har asynkrona FIFO-konstruktioner använts. Denna lösningsmetod har visat sig innehålla en del brister vid tillämpning på höghastighets system, vilket ledde till att synkrona FIFOn började ersätta asynkrona FIFOn. </p><p>Den synkrona arkitekturen har samma funktonalitet som de asynkrona typerna med fördelar som högre hastighet och enklare gränssnitt. </p><p>I rapporten har olika FIFO-konstruktioner behandlats och jämförelser har gjorts mellan synkrona och asynkrona arkitekturer. Det vid ISY konstruerade SRAM-minnet har sedan avgjort vilken typ av FIFO-arkitektur som varit bäst lämpad för implementering. </p><p>Det implementerade FIFO-minnet ordnar indata- och utdataflöden till ett enkelports SRAM-minne på 256 ord med 16 bitar per ord.</p> / <p>Previous implementations of FIFO-architectures has often been asynchronous FIFO-constructions. This method has some limitations in high speed systems. Instead synchronous FIFOs has more and more replaced asynchronous FIFOs. </p><p>The synchronous architecture has the same features as the asynchronous but with advantages such as higher speed and simplified interface. </p><p>In the report different types of FIFO-constructions has been studied and comparison between synchronous and asynchronous architectures has been done. The memory unit developed by ISY decided which FIFO-architecture that were best suited for the implementation. </p><p>The implemented FIFO-memory arrange in- and outdataflow to a single-port SRAM memory containing 256 words with 16 bits per word.</p>
17

A Novel Method For 2-18 Ghz Switched Multiplexer Design

Alicioglu, Bulent 01 September 2012 (has links) (PDF)
A novel topology is developed and used to design a switched multiplexer. In the new topology there are two noncontiguous switched multiplexer modules containing the channels 2-4 GHz, 6-8 GHz, 10-12 GHz and 14-16 GHz named as odd channels and 4-6 GHz, 8-10 GHz, 12-14 GHz and 16-18 GHz, named as even channels to improve isolation between adjacent channels. The input signal is split at input into the two multiplexer and the outputs of the multiplexers are combined by 2-18 GHz power dividers. The input and output multiplexers are combined through switch + Low Noise Amplifier + attenuator blocks which are also used for amplitude equalization. The input/output multiplexers are designed using a novel technique that transforms a contiguous manifold multiplexer into non-contiguous multiplexers with 2 GHz bandwidth to form guard bands between channels to improve isolation. The HP outputs of the channels are split by LP-HP diplexers with corner frequencies at the centers of the channels. Then only the LP outputs of these diplexers are fed to the output to form a non-contiguous multiplexers. The HP outputs of LP-HP diplexers are terminated in 50 ohms. The incorporation of LP-HP diplexer to form noncontiguous channels is a novel approach which avoids interaction of channels. The diplexers forming the switched multiplexer are designed using a novel approach which incorporate open circuited parallel coupled line as diplexing element. This structure acts as an integral part of the diplexer and contributes its performance. The LP-HP diplexers are designed and fabricated successfully in suspended stripline. The implemented LP-HP diplexers are then combined to form the even and odd channel multiplexers. The measured results of the individual diplexers are then combined with attenuator+Amplifier blocks to form the circuit model of the targeted switched multiplexer yielding successful performance. Thus, the design is complete and ready for the realization of a switched multiplexer.
18

FIFO-kostruktion baserat på ett enkel-ports SRAM / FIFO-construction based on a single-port SRAM

Duman, Yusuf January 2003 (has links)
Vid implementeringar av FIFO-arkitekturer har asynkrona FIFO-konstruktioner använts. Denna lösningsmetod har visat sig innehålla en del brister vid tillämpning på höghastighets system, vilket ledde till att synkrona FIFOn började ersätta asynkrona FIFOn. Den synkrona arkitekturen har samma funktonalitet som de asynkrona typerna med fördelar som högre hastighet och enklare gränssnitt. I rapporten har olika FIFO-konstruktioner behandlats och jämförelser har gjorts mellan synkrona och asynkrona arkitekturer. Det vid ISY konstruerade SRAM-minnet har sedan avgjort vilken typ av FIFO-arkitektur som varit bäst lämpad för implementering. Det implementerade FIFO-minnet ordnar indata- och utdataflöden till ett enkelports SRAM-minne på 256 ord med 16 bitar per ord. / Previous implementations of FIFO-architectures has often been asynchronous FIFO-constructions. This method has some limitations in high speed systems. Instead synchronous FIFOs has more and more replaced asynchronous FIFOs. The synchronous architecture has the same features as the asynchronous but with advantages such as higher speed and simplified interface. In the report different types of FIFO-constructions has been studied and comparison between synchronous and asynchronous architectures has been done. The memory unit developed by ISY decided which FIFO-architecture that were best suited for the implementation. The implemented FIFO-memory arrange in- and outdataflow to a single-port SRAM memory containing 256 words with 16 bits per word.
19

Avaliação de critérios de compatibilidade entre pares de primers para otimização de sistemas multiplex de genotipagem / Evaluation of compatibility criteria among primers pairs for optimizing multiplex genotyping systems

BARBOSA, Ana Clara de Oliveira Ferraz 12 January 2010 (has links)
Made available in DSpace on 2014-07-29T15:16:37Z (GMT). No. of bitstreams: 1 AnaClaraferraz.pdf: 1870286 bytes, checksum: d17e1fe96ee32ca1852c51743beff160 (MD5) Previous issue date: 2010-01-12 / The progress of Molecular Biology and Genetics provided the appearance of several molecular markers that detect the genetic polymorphism directly at DNA. Among these markers are the microsatellites (SSR), which are distinguished by their high degree of polymorphism. The use of these markers for individual genotyping has evolved into multiplex systems, which allow many SSR fragments to be detected and analyzed simultaneously. Currently there are several articles in literature discussing the criteria to be used in the primer design for use in PCR, as well as various softwares are available for this end. However, there are few studies and tools for the analysis of compatibility between pairs of primers for use in multiplex systems, where multiple fragments are simultaneously amplified using PCR. This paper evaluated different criteria for compatibility between pairs of primers. A set of 74 combinations of pairs of primers, involving the amplification of 94 SSR loci were evaluated in duplex systems. The same combinations were evaluated according to different criteria, including the degree of complementarity between primers, the magnitude of differences of denaturation temperatures (Tm) and the tendency to annealing between pairs of primers based on the Gibbs free energy resulting from the association between them. The comparison between the different criteria allowed the identification of a set of criteria with positive predictive value equal to 94%. These criteria were implemented for use in a software called Multiplexer, which from the analysis in sequence of pairs of primers, suggests compatible combinations for use in multiplex genotyping systems. Using this tool can significantly reduce the costs related to laboratory activities for genotyping using PCR. / Os avanços da Biologia Molecular e da Genética proporcionaram o surgimento de diversos marcadores moleculares que detectam o polimorfismo genético diretamente no DNA. Entre estes marcadores se encontram os microssatélites (SSR), que se destacam pelo seu elevado grau de polimorfismo. O uso desses marcadores para fins de genotipagem individual tem evoluído para sistemas multiplex, os quais permitem que vários fragmentos SSR sejam detectados e analisados simultaneamente. Atualmente são abundantes na literatura artigos que discutem os critérios a serem utilizados no desenho de pares de primers para aplicação em PCR, bem como estão disponíveis diversos softwares para este fim. No entanto, ainda são escassos os estudos e ferramentas destinados à análise de compatibilidade entre pares de primers para aplicação em sistemas multiplex, onde vários fragmentos são amplificados simultaneamente por PCR. Neste trabalho são avaliados diferentes critérios de compatibilidade entre pares de primers. Um conjunto de 74 combinações de pares de primers, envolvendo a amplificação de 94 locos SSR foram avaliados em sistemas duplex. As mesmas combinações foram avaliadas segundo diferentes critérios, incluindo o grau de complementariedade entre primers, magnitude das diferenças de temperaturas de desnaturação (Tm) e a tendência ao anelamento entre pares de primers com base na energia livre de Gibbs resultante da associação entre eles. A comparação entre os diferentes critérios permitiu a identificação de um conjunto de critérios com valor preditivo positivo igual a 94%. Estes critérios foram implementados para utilização em um software denominado Multiplexer, que a partir da análise de sequências de pares de primers, sugere combinações compatíveis para a utilização em sistemas de genotipagem multiplex. O uso dessa ferramenta pode reduzir consideravelmente os custos laboratoriais relativos às atividades de genotipagem utilizando PCR.
20

FLIGHT INSTRUMENTATION TELEMETRY FOR AEROSPACE APPLICATION

RAJYALAKSHMI, P. S., RAJANGAM, R. K. 10 1900 (has links)
International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada / In Aerospace missions it is often required to have a flexible telemetry system for carrying out flight test on aircraft, in which the bit rate, sampling rate and the number of channels can be programmed. This enables the pilot of the aircraft to reconfigure the telemetry system to suit any particular test missions. An L-Band PCM/FM Telemetry System containing a Stored Programme Multiplexer, 12 bit ADC and other digital interfaces for carrying out the measurements on Speed, Events, etc has been developed as a flight instrumentation telemetry for HAL, India. This paper not only presents complete details of the system, which was qualified to meet MIL-5422 levels but also the performance of the system during actual aircraft missions.

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