<p>This masters thesis investigates the possibility to estimate the ethanol content in the fuel using ion currents. Flexible fuel cars can be run on gasoline-ethanol blends with an ethanol content from0 to 85 percentage. It is important for the engine control system to have information about the fuel. In todays cars the measurements of the fuel blend are done by a sensor. If it is possible to do this with ion currents this can be used to detect if the sensor is broken, and then estimate the ethanol content until the sensor gets fixed. The benefit</p><p>of using ion currents is that the signal is measured directly from the spark plug and therefore no extra hardware is needed. To be able to see how the ethanol ratio affects the ion currents, the dependencies of the operating point have been investigated. This has been done by a literature review and by measurements in a Saab 9-3. Engine speed, load, ignition timing, lambda and spark plugs effects on the ion currents are especially studied. A black box model for the ion currents dependence on operating point is developed. This model describes the engine speed, load and ignition timing dependencies well, but it can not be used to estimate the ethanol ratio.</p>

<p>Direct semiconductor wafer bonding has emerged as a technology to meet the demand foradditional flexibility in materials integration. The applications are found in microelectronics, optoelectronics and micromechanics. For instance, wafer bonding is used to produce silicon-on-insulator (SOI) wafers. Wafer bonding is also interesting to use for combining dissimilar semiconductors, such as Si and InP, with different dictated optical, electronic and mechanicalproperties. This enables a completely new freedom in the design of components and systems, e.g. for high performance optoelectronic integrated circuits (OEIC). Although wafer bonding has proved to be a useful and versatile tool, the high temperature annealing that is needed to achieve reliable properties sometimes hampers its applicability. Therefore, low temperature wafer bonding procedures may further qualify this technology.</p><p>In the present thesis, low temperature wafer bonding procedures using oxygen plasma surface activation have been studied. A specially designed fixture was adopted enabling <i>in situ </i>oxygen plasma wafer bonding. Oxygen plasma surface activation was seen to indeed yield high Si-Si bonding-strength at low temperatures. Here, the optimisation of the plasma parameters was shown to be the key to improved results. Furthermore, dependence of wafer bonded Si p-n junctions on the annealing temperature was investigated. InP-to-Si wafer bonding is also presented within this thesis. High temperature annealing was seen to induce severe material degradation. However, using oxygen plasma assisted wafer bonding reliable InP-to-Si integration was achieved already at low temperature, thereby circumventing the problems associated with the lattice and thermal mismatch that exist between these materials. As a result, low temperature InP-based epitaxial-layer transferring to Si could be presented. Finally, high-quality SiO2 insulator on InP and Si was realised at low temperatures.</p><p>It is concluded that low temperature oxygen plasma assisted wafer bonding is an interesting approach to integrate dissimilar materials, for a wide range of applications.</p>

PMOS and NMOS mobility characteristics of the dual channel (strained Si/strained Ge) heterostructure have been reviewed. It is shown that the dual channel heterostructure can provide substantially enhanced mobilities for both electrons and holes. However, germanium interdiffusion from the germanium rich buried layer into the underlying buffer layer could potentially reduce the hole mobility enhancements. / Singapore-MIT Alliance (SMA)

Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Translated from Korean. Includes bibliographical references (leaves 157-160).

Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Includes bibliographical references (leaves 159-162).

Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Translated from Korean. Includes bibliographical references (leaves 164-167).

Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Includes bibliographical references (leaves 167-172).

Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Translated from Korean. Includes bibliographical references (leaves 186-190).

Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2004. / Includes abstract and vita. Includes bibliographical references (leaves 169-173).

The aim is to share experience gained when simulating (and doing measurements on) the turbocharged SI-engine as well as describing the limits of current state of the technology. In addition an overview of current boosting systems is provided. The target readers of this text are engineers employed in the engine industry as well as academia who will get in contact, or is experienced, with 1D engine performance simulation and/or boosting systems. Therefore the text requires general knowledge about engines. The papers included in the thesis are, in reverse chronological order: [8] SAE 2005-XX-XXX Calculation accuracy of pulsating flow through the turbine of SI-engine turbochargers - Part 2 Measurements, simulation correlations and conclusions Westin &amp; Ångström To be submitted to the 2005 SAE Powertrain and Fluid Systems Conference in San Antonio [7] SAE 2005-01-2113 Optimization of Turbocharged Engines’ Transient Response with Application on a Formula SAE / Student engine Westin &amp; Ångström Approved for publication at the 2005 SAE Spring Fuels and Lubricants Meeting in Rio de Janeiro [6] SAE 2005-01-0222 Calculation accuracy of pulsating flow through the turbine of SI-engine turbochargers - Part 1 Calculations for choice of turbines with different flow characteristics Westin &amp; Ångström Published at the 2005 SAE World Congress in Detroit April 11-14, 2005 [5] SAE 2004-01-0996 Heat Losses from the Turbine of a Turbocharged SI-Engine – Measurements and Simulation Westin, Rosenqvist &amp; Ångström Presented at the 2004 SAE World Congress in Detroit March 8-11, 2004 [4] SAE 2003-01-3124 Simulation of a turbocharged SI-engine with two software and comparison with measured data Westin &amp; Ångström Presented at the 2003 SAE Powertrain and Fluid Systems Conference in Pittsburgh [3] SIA C06 Correlation between engine simulations and measured data - experiences gained with 1D-simulations of turbocharged SI-engines Westin, Elmqvist &amp; Ångström Presented at the SIA International Congress SIMULATION, as essential tool for risk management in industrial product development in Poissy, Paris September 17-18 2003 [2] IMechE C602/029/2002 A method of investigating the on-engine turbine efficiency combining experiments and modelling Westin &amp; Ångström Presented at the 7th International Conference on Turbochargers and Turbocharging in London 14-15 May, 2002 [1] SAE 2000-01-2840 The Influence of Residual Gases on Knock in Turbocharged SI-Engines Westin, Grandin &amp; Ångström Presented at the SAE International Fall Fuels and Lubricants Meeting in Baltimore October 16-19, 2000 The first step in the investigation about the simulation accuracy was to model the engine as accurately as possible and to correlate it against as accurate measurements as possible. That work is covered in the chapters 3 and 5 and in paper no. 3 in the list above. The scientific contribution here is to isolate the main inaccuracy to the simulation of turbine efficiency. In order to have anything to compare the simulated turbine efficiency against, a method was developed that enables calculation of the CA-resolved on-engine turbine efficiency from measured data, with a little support from a few simulated properties. That work was published in papers 2 and 8 and is the main scope of chapter 6 in the thesis. The scientific contributions here are several: · The application on a running SI-engine is a first · It was proven that CA-resolution is absolutely necessary in order to have a physically and mathematically valid expression for the turbine efficiency. A new definition of the time-varying efficiency is developed. · It tests an approach to cover possible mass accumulation in the turbine housing · It reveals that the common method for incorporating bearing losses, a constant mechanical efficiency, is too crude. The next step was to investigate if different commercial codes differ in the results, even though they use equal theoretical foundation. That work is presented in chapter 4, which corresponds to paper 4. This work has given useful input to the industry in the process of choosing simulation tools. The next theory to test was if heat losses were a major reason for the simulation accuracy. The scientific contribution in this part of the work was a model for the heat transport within the turbocharger that was developed, calibrated and incorporated in the simulations. It was concluded that heat losses only contributed to a minor part of the inaccuracy, but that is was a major reason for a common simulation error of the turbine outlet temperature, which is very important when trying to simulate catalyst light off. This work was published in paper 5 and is covered in chapter 7. Chapter 8, and papers 6 and 8, covers the last investigation of this work. It is a broad study where the impact of design changes of both manifold at turbines on both simulation accuracy as well as engine performance. The scientific contribution here is that the common theory that the simulation inaccuracy is proportional to the pulsation amplitude of the flow is non-valid. It was shown that the reaction was of minor importance for the efficiency of the turbine in the pulsating engine environment. Furthermore it presents a method to calculate internal flow properties in the turbine, by use of a steady-flow design software in a quasi-steady procedure. Of more direct use for the industry is important information of how to design the manifolds as well as it sheds more light on how the turbine works under unsteady flow, for instance that the throat area is the single most important property of the turbine and that the system has a far larger sensitivity to this parameter than to any other design parameters of the turbine. Furthermore it was proven that the variation among individual turbines is of minor importance, and that the simulation error was of similar magnitude for different turbine manufacturers. Paper 7, and chapter 9, cover a simulation exercise where the transient performance of turbocharged engines is optimised with help from factorials. It sorts out the relative importance of several design parameters of turbocharged engines and gives the industry important information of where to put the majority of the work in order to maximize the efficiency in the optimisation process. Overall, the work presented in this thesis has established a method for calibration of models to measured data in a sequence that makes the process efficient and accurate. It has been shown that use of controllers in this process can save time and effort tenfold or more. When designing turbocharged engines the residual gas is a very important factor. It affects both knock sensitivity and the volumetric efficiency. The flow in the cylinder is in its nature of more dimensions than one and is therefore not physically modelled in 1D codes. It is modelled through models of perfect mixing or perfect displacement, or at a certain mix between them. Before the actual project started, the amount of residual gases in an engine was measured and it’s influence on knock was established and quantified. This was the scope of paper 1. This information has been useful when interpreting the model results throughout the entire work.