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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

High Speed Clock and Data Recovery Techniques

Abiri, Behrooz 01 December 2011 (has links)
This thesis presents two contributions in the area of high speed clock and data recovery systems. These contributions are focused on the fast phase recovery and adaptive equalization techniques. The first contribution of this thesis is an adaptive engine for a 2x blind sampling receiver. The proposed adaptation engine is able to find the phase-dependent DFE coefficients of the receiver on the fly. The second contribution is a burst-mode clock and data recovery architecture which uses an analog phase interpolator. The proposed burst-mode CDR is capable of locking to the first data transition it receives. The phase interpolator uses the inherent timing information in the data transition to rotate the phase of a reference clock and align it with the incoming data edge. The feasibility of the concept is demonstrated through fabrication and measurements.
142

Associations among neutrophil function, metabolic indicators, and reproductive health in dairy cows

Wittrock, Julie 10 May 2012 (has links)
This thesis is an investigation of the interactions of insulin resistance (IR), metabolic markers, neutrophil function, and reproductive health in peripartum dairy cows, including the evaluation of a hand-held glucometer for diagnosis of IR. The neutrophil functions of interest were oxidative burst and phagocytosis capacity, and reproductive diseases were endometritis and cervicitis. A total of 81 Holstein cows were enrolled 3 wk prior to expected calving date from November 2010 until October 2011, and were followed until 5 wk postpartum. Known markers of IR, neutrophil function, and disease were monitored through this period. The hand-held glucometer was identified as a useful alternative to laboratory measurements of glucose. Markers of IR influenced phagocytosis capacity and reproductive disease. High haptoglobin concentrations were associated with increased risk of reproductive disease and diminished oxidative burst function. Metabolically related inhibition of neutrophil function may be important in development of reproductive disease. / National Sciences and Engineering Research Council of Canada, Ontario Graduate Scholarship Program
143

A Dimmable LED Driver For Visible Light Communication Based On the LLC Resonant Converter

Zhao, Shuze 11 December 2013 (has links)
This work presents a new wireless Visible Light Communication lighting system targeted to future Smart Buildings. A digitally controlled LLC resonant dc-dc converter targeted to white LED luminaires is demonstrated. Visible Light Communication is implemented with minimal incremental cost, by operating the LLC converter in burst mode, without causing any visible disturbance. The converter operates with a regulated average LED current by adjusting the switching frequency, while the burst pulse timing is controlled to minimize the current disturbance and minimize the value of the output capacitor. Variable Pulse Position Modulation is used to modulate the data, while supporting a range of dimming settings. A digital demodulation scheme that supports variable frequency transmission is demonstrated. The 80 W, 400 V to 23 V converter experimental prototype has a peak efficiency of 93.8 %. The bit error rate of the complete system is fully characterized versus distance and angle.
144

Neural networks and early fast Doppler for prediction in meteor-burst communications systems.

Fraser, David Douglas. January 1994 (has links)
In meteor-burst communications systems, the channel is bursty with a continuously fluctuating signal-to-noise ratio. Adaptive data rate systems attempt to use the channel more optimally by varying the bit rate. Current adaptive rate systems use a method of closed-loop decision-feedback to control the transmitted data rate. It is proposed that an open-loop adaptive data rate system without a decision feedback path may be possible using implicit channel information carried in the first few milliseconds of the link establishment probe signal. The system would have primary application in low-cost half-duplex telemetry systems. It is shown that the key elements in such a system would be channel predictors. The development of these predictors is the focus of this research. Two novel methods of predicting channel parameters are developed. The first utilises early fast Doppler information that precedes many long duration, large signal-to-noise-ratio overdense trails. The presence of early fast Doppler at the trail commencement is used as a toggle to operate at a higher data rate. Factors influencing the use of early fast Doppler for this purpose are also presented. The second method uses artificial neural networks. Data measured during trail formation is processed and presented to the neural networks for prediction of trail parameters. Several successful neural networks are presented which predict trail type, underdense or overdense, and peak trail amplitude from the first 50ms of the trail's lifetime. This method allows better estimation of the developing trail. This fact can be used to implement a multi-rate open-loop adaptive data rate system. / Thesis (Ph.D.)-University of Natal, Durban, 1994.
145

A Dimmable LED Driver For Visible Light Communication Based On the LLC Resonant Converter

Zhao, Shuze 11 December 2013 (has links)
This work presents a new wireless Visible Light Communication lighting system targeted to future Smart Buildings. A digitally controlled LLC resonant dc-dc converter targeted to white LED luminaires is demonstrated. Visible Light Communication is implemented with minimal incremental cost, by operating the LLC converter in burst mode, without causing any visible disturbance. The converter operates with a regulated average LED current by adjusting the switching frequency, while the burst pulse timing is controlled to minimize the current disturbance and minimize the value of the output capacitor. Variable Pulse Position Modulation is used to modulate the data, while supporting a range of dimming settings. A digital demodulation scheme that supports variable frequency transmission is demonstrated. The 80 W, 400 V to 23 V converter experimental prototype has a peak efficiency of 93.8 %. The bit error rate of the complete system is fully characterized versus distance and angle.
146

炭素14と宇宙線変動 : 奈良時代の異変

Nakamura, Toshio, Nagaya, Kentarou, Miyake, Fusa, Masuda, Kimiaki, 中村, 俊夫, 永冶, 健太朗, 三宅, 芙沙, 増田, 公明 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
147

High Speed Clock and Data Recovery Techniques

Abiri, Behrooz 01 December 2011 (has links)
This thesis presents two contributions in the area of high speed clock and data recovery systems. These contributions are focused on the fast phase recovery and adaptive equalization techniques. The first contribution of this thesis is an adaptive engine for a 2x blind sampling receiver. The proposed adaptation engine is able to find the phase-dependent DFE coefficients of the receiver on the fly. The second contribution is a burst-mode clock and data recovery architecture which uses an analog phase interpolator. The proposed burst-mode CDR is capable of locking to the first data transition it receives. The phase interpolator uses the inherent timing information in the data transition to rotate the phase of a reference clock and align it with the incoming data edge. The feasibility of the concept is demonstrated through fabrication and measurements.
148

Mechanical Characterization Of Filament Wound Composite Tubes By Internal Pressure Testing

Karpuz, Pinar 01 May 2005 (has links) (PDF)
The aim of this study is to determine the mechanical characteristics of the filament wound composite tubes working under internal pressure loads, generating data for further investigation with a view of estimating the remaining life cycle of the tubes during service. Data is generated experimentally by measuring the mechanical behavior like strains in hoop direction, maximum hoop stresses that are formed during internal pressure loading. Results have been used to identify and generate the necessary data to be adopted in the design applications. In order to determine these parameters, internal pressure tests are done on the filament wound composite tube specimens according to ASTM D 1599-99 standard. The test tubes are manufactured by wet filament winding method, employing two different fiber types, two different fiber tension settings and five different winding angle configurations. The internal pressure test results of these specimens are studied in order to determine the mechanical characteristics, and the effects of the production variables on the behavior of the tubes. Pressure tests revealed that the carbon fiber reinforced composite tubes exhibited a better burst performance compared to the glass fiber reinforced tubes, and the maximum burst performance is achieved at a winding angle configuration of [&plusmn / 54&deg / ]3[90&deg / ]1. In addition, the tension setting is found not to have a significant effect on the burst performance. The burst pressure data and the final failure modes are compared with the results of the ASME Boiler and Pressure Vessel Code laminate analysis, and it was observed that there is a good agreement between the laminate analysis results and the experimental data. The stress &ndash / strain behavior in hoop direction are also studied and hoop elastic constants are determined for the tubes.
149

The role of neutrophil primining and neutrophil antibodies in the pathogenesis of Transfusion-Related Acute Lung Injury (TRALI)

Yoke Lin Fung Unknown Date (has links)
No description available.
150

Analysis of the modified Cramer Rao bound for burst mode symbol clock synchronisation

Doan, John January 2007 (has links)
This thesis presents an analysis of the Modified Cramer Rao Bound (MCRB) for synchroniser performance in burst mode communication applications. This is accomplished by introducing the topic of burst mode communications and its practical applications, discussing the importance of synchronisation, presenting a model through which the mathematical analysis of this thesis is based upon, deriving a set of equations which can be used to calculate the MCRB and finally by performing various calculations of the MCRB with different parameters to examine their effects on the MCRB. The methods presented in this thesis are different from those presented in existing literature, which generally do not address the issue of burst mode synchronisation directly. The differences between the methods presented in this thesis and those of existing literature is also discussed.

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