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This thesis investigates the suitability of global navigation satellite system (GNSS) signals for cellular phone location. The requirement is to determine and report the location of a phone during an emergency call.<p> The thesis analyzes acquisition and tracking techniques suitable for very weak signals as received by a cellular phone indoors. The L1 and L5 signals from GPS satellites and the L1 signal from Galileo satellites are considered. It is shown that long integration times and coherent integration are required for the weakest expected signals. Long coherent integration times require a precise knowledge of the Doppler shift due to the range rate of the satellite. The tolerance to Doppler shift can be increased by using FFTs in the analysis of the data. Non-coherent averaging techniques improve the Doppler tolerance but compared to coherent averaging, the loss of signal to noise ratio is too large for the weakest signals.<p> Coherent averaging of the GPS L1 signal requires data removal that can be accomplished with assistance from the cellular network. The GPS L5 and Galileo L1 signals include a data-less or pilot channel. The GPS L5 pilot channel includes a 20 bit Neuman Hoffman code with a bit period of 1 ms. This code has to be acquired or removed before coherent averaging. Similarly the Galileo pilot channel includes a 25 bit short code.<p> Once code acquisition has been accomplished, it is necessary to track the signals from at least four satellites for long enough to compute a position estimate. A discussion of tracking techniques is included to show the signal to noise ratio limitations for adequate tracking accuracy.<p> The results show that GNSS signals are suitable for cellular phone location in a large number of situations. Increased receiver sensitivity would permit location in additional situations. In rural situations GNSS may be the only available option.

This thesis investigates the suitability of global navigation satellite system (GNSS) signals for cellular phone location. The requirement is to determine and report the location of a phone during an emergency call.<p> The thesis analyzes acquisition and tracking techniques suitable for very weak signals as received by a cellular phone indoors. The L1 and L5 signals from GPS satellites and the L1 signal from Galileo satellites are considered. It is shown that long integration times and coherent integration are required for the weakest expected signals. Long coherent integration times require a precise knowledge of the Doppler shift due to the range rate of the satellite. The tolerance to Doppler shift can be increased by using FFTs in the analysis of the data. Non-coherent averaging techniques improve the Doppler tolerance but compared to coherent averaging, the loss of signal to noise ratio is too large for the weakest signals.<p> Coherent averaging of the GPS L1 signal requires data removal that can be accomplished with assistance from the cellular network. The GPS L5 and Galileo L1 signals include a data-less or pilot channel. The GPS L5 pilot channel includes a 20 bit Neuman Hoffman code with a bit period of 1 ms. This code has to be acquired or removed before coherent averaging. Similarly the Galileo pilot channel includes a 25 bit short code.<p> Once code acquisition has been accomplished, it is necessary to track the signals from at least four satellites for long enough to compute a position estimate. A discussion of tracking techniques is included to show the signal to noise ratio limitations for adequate tracking accuracy.<p> The results show that GNSS signals are suitable for cellular phone location in a large number of situations. Increased receiver sensitivity would permit location in additional situations. In rural situations GNSS may be the only available option.

Interactions between Mn12–acetate molecular magnets and thin gold films have been explored in light of the theory of weak localization. Low-temperature measurements of the magnetoresistance of gold films of varying thicknesses, with and without the presence of a surface layer of Mn12–acetate, have been performed using a dilution refrigerator. Quantitative fits to the data using the predictions of weak localization theory were performed using a least-squares fit method in order to determine characteristic times for elastic, inelastic, spin-orbit and spin scattering events within the gold. These data indicate that the presence of Mn12–acetate on the surface of the gold film leads to a significant enhancement of the spin scattering within the gold films.

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Flameless combustion technology has been developed over the past twenty years achieving low-NOx emissions and high energy efficiency for industrial applications. In the present work, three aspects of flameless combustion were examined based on a burner employing the Strong-Jet/Weak-Jet (SJ/WJ) configuration. In the first part of the work, a 3-D SJ/WJ physical model was developed in the Lagrangian perspective for an isothermal pair of free jets. The model was used to predict the WJ trajectory, identify important design/operation factors, and estimate the extent of mixing in the main combustion region (confluence region). The model was also validated with experimental data and showed excellent agreement over a wide range of flow conditions. In the second part of the work, a simplified chemical kinetic model was developed for the flameless combustion of natural gas. A detailed chemical reaction mechanism (GRI Mech 3.0) was successfully reduced to a skeletal chemical reaction mechanism under flameless combustion conditions by Principal Component Analysis, sensitivity analysis and reaction flow analysis. The skeletal mechanism was further simplified to a set of 2-D manifolds by Trajectory-Generated Low-Dimensional Manifolds (TGLDM) method. The set of 2-D manifolds was tested by the Batch Reactor (BR) and Perfect Stirred Reactor (PSR) models. From the BR model test, it was found that the chemical reaction rates were well represented by the 2-D manifolds. The effect of the physical perturbation, tested by PSR model, could be handled by the perpendicular projection instead of the orthogonal projection because both showed similar discrepancies with the skeletal mechanism. In the final part of the work, the steady-state Reynolds-Averaged Navier-Stokes (RANS) simulation was conducted for the turbulent flameless combustion in the SJ/WJ furnace, based on the Probability Density Function (PDF)/Mixing approach. The set of 2-D manifolds and Conditional Source-term Estimate (CSE) method were used for the combustion reaction and the estimation of the mean production/destruction rate, respectively. This CSE-TGLDM model provided good predictions of major species concentrations. However, the gas temperatures and CO concentrations were highly over-predicted. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2010-09-23 11:05:21.884

The Q-weak experiment at Thomas Jefferson National Accelerator Facility (USA) will make a precision determination of the proton weak charge with approximately 4% combined statistical and systematic uncertainties via a measurement of the parity violating asymmetry in elastic electron-proton scattering at very low momentum transfer and forward angle. This will allow an extraction of the weak mixing angle at Q^2=0.026 (GeV/c)^2 to approximately 0.3%. The weak mixing angle is a fundamental parameter in the Standard Model of electroweak interactions. At the proposed accuracy, a measured deviation of this parameter from the predicted value would indicate new physics beyond what is currently described in the Standard Model. Without deviation from the predicted value, this measurement would place stringent limits on possible extensions to the Standard Model and constitute the most precise measurement of the proton's weak charge to date. The key experimental apparatus include a liquid hydrogen target, a toroidal magnetic spectrometer and a set of eight Cerenkov detectors. The Cerenkov detectors form the main detector system for the Q-weak experiment and are used to measure the parity violating asymmetry during the primary Q-weak production runs. The Cerenkov detectors form the main subject of this thesis. Following a brief introduction to the experiment, the design, development, construction, installation, and testing of this detector system will be discussed in detail. This is followed by a detailed discussion of detector diagnostic data analysis and the corresponding detector performance. The experiment has been successfully constructed and commissioned, and is currently taking data. The thesis will conclude with a discussion of the preliminary analysis of a small portion of the liquid hydrogen data.

In the two years 1994 and 2013 the focus of the Swedish media in the school debate has been on segregation, freedom of choice, and support for weak students. In 2013 while the media was still united on the above issues the overall emphasis is on profitability. In 1994 the focus was more on weak students who in 2013 are considered unprofitable. The purpose of this essay is to study the Swedish media and their debate on Swedish schools and witch concepts related to "one school that fits all" in the year 1994 and also in 2013. We have analysed related articles and their concepts, norms, and values to see if there are any differences between their focus on the said issues in the two years. We have also studied the ideas and concepts that came under scrutiny and discussion in these two years, and shall investigate if there are differences in the debates conducted in 1994 and those conducted in 2013.

The Q-weak experiment at Thomas Jefferson National Accelerator Facility (USA) will make a precision determination of the proton weak charge with approximately 4% combined statistical and systematic uncertainties via a measurement of the parity violating asymmetry in elastic electron-proton scattering at very low momentum transfer and forward angle. This will allow an extraction of the weak mixing angle at Q^2=0.026 (GeV/c)^2 to approximately 0.3%. The weak mixing angle is a fundamental parameter in the Standard Model of electroweak interactions. At the proposed accuracy, a measured deviation of this parameter from the predicted value would indicate new physics beyond what is currently described in the Standard Model. Without deviation from the predicted value, this measurement would place stringent limits on possible extensions to the Standard Model and constitute the most precise measurement of the proton's weak charge to date. The key experimental apparatus include a liquid hydrogen target, a toroidal magnetic spectrometer and a set of eight Cerenkov detectors. The Cerenkov detectors form the main detector system for the Q-weak experiment and are used to measure the parity violating asymmetry during the primary Q-weak production runs. The Cerenkov detectors form the main subject of this thesis. Following a brief introduction to the experiment, the design, development, construction, installation, and testing of this detector system will be discussed in detail. This is followed by a detailed discussion of detector diagnostic data analysis and the corresponding detector performance. The experiment has been successfully constructed and commissioned, and is currently taking data. The thesis will conclude with a discussion of the preliminary analysis of a small portion of the liquid hydrogen data.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. Description based on print version record. Includes bibliographical references.