Resonant circuits are an important component of almost every radio circuit, and the determination of the properties of resonant circuits is an important measurement problem. Circuits with distributed constants., such as transmission lines, may resonate if they are properly terminated. A resonant transmission line which is analogous to the familiar LRC series resonant circuit is called a reaction, or absorbtion, type resonator. [...]

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A study of the mixing of subsonic jets with cold streams has been made. An apparatus was constructed for the mixing of such jets at angles with streams. Jets with initial temperatures up to 1075 °K were directed at right angle to cold air streams at various velocities and the effects of some of the factors influencing the mixing have been determined and analysed. [...]

The experimental work described in the thesis consisted of a series of tests of model footings on dry silt of various porosities. It was done from the point of view of settlement-pressure relationship. Also, one of the theories of settlement is examined, and the results of the tests are compared with that theory. The principal factors affecting the tests are pointed out, and suggestions are made to guide further studies of the subject.

The behaviour of quartz crystal units subjected to high drive levels and prolonged oscillation periods, as well as their subsequent recovery from these two conditions, were investigated. Abnormal oscillatory stresses were found to produce an increase in the internal friction and a consequent decrease in the dynamic modulus of the quartz. These effects appear in the crystal units, as a higher effective resistance and a depressed resonant frequency.

<p> Since 1966, five major regulations have been enacted in the United States (U.S.) to regulate food packaging. The U.S. Food and Drug Administration and the U.S. Department of Agriculture regulate items required on a label and what claims can be made about a product. Although there are a number of items that are regulated on a product label, much of the label is cluttered with marketing jargon and non-regulated information.</p><p> This project illustrates how one company has used the DMAIC (Define, Measure, Analyze, Improve, and Control) method to continuously improve a beverage product label in conjunction with a cross-functional team from the Marketing, Research and Development, Quality, and Legal departments. The result is a cleaner label that is a compromise between regulatory requirements and marketing requests. The open communication between departments has fostered an environment for continuous improvement of the product label.</p>

There is growing interest in reducing the environmental and human-­‐health impacts resulting from electricity generation. Renewable energy, energy efficiency, and energy conservation are all commonly suggested solutions. Such interventions may provide health and environmental benefits by displacing emissions from conventional power plants. However, the generation mix varies considerably from region to region and emissions vary by the type and age of a generator. Thus, the benefits of an intervention will depend on the specific generators that are displaced, which vary depending on the timing and location of the intervention. Marginal emissions factors (MEFs) give a consistent measure of the avoided emissions per megawatt-­‐hour of displaced electricity, which can be used to evaluate the change in emissions resulting from a variety of interventions. This thesis presents the first systematic calculation of MEFs for the U.S. electricity system. Using regressions of hourly generation and emissions data from 2006 through 2011, I estimate regional MEFs for CO2, NOx, and SO2, as well as the share of marginal generation from coal-­‐, gas-­‐, and oil-­‐fired generators. This work highlights significant regional differences in the emissions benefits of displacing a unit of electricity: compared to the West, displacing one megawatt-­‐hour of electricity in the Midwest is expected to avoid roughly 70% more CO2, 12 times more SO2, and 3 times more NOx emissions. I go on to explore regional variations in the performance of wind turbines and solar panels, where performance is measured relative to three objectives: energy production, avoided CO2 emissions, and avoided health and environmental damages from criteria pollutants. For 22 regions of the United States, I use regressions of historic emissions and generation data to estimate marginal impact factors, a measure of the avoided health and environmental damages per megawatt-­‐ hour of displaced electricity. Marginal impact factors are used to evaluate the effects of an additional wind turbine or solar panel in the U.S. electricity system. I find that the most attractive sites for renewables depend strongly on one’s objective. A solar panel in Iowa displaces 20% more CO2 emissions than a panel in Arizona, though energy production from the Iowa panel is 25% less. Similarly, despite a modest wind resource, a wind turbine in West Virginia is expected to displace 7 times more health and environmental damages than a wind turbine in Oklahoma. Finally, I shift focus and explore the economics of small-­‐scale cogeneration, which has long been recognized as a more efficient alternative to central-­‐station power. Although the benefits of distributed cogeneration are widely cited, adoption has been slow in the U.S. Adoption could be encouraged by making cogeneration more economically attractive, either by increasing the expected returns or decreasing the risks of such investments. I present a case study of a 300-­‐kilowatt cogeneration unit and evaluate the expected returns from: demand response, capacity markets, regulation markets, accelerated depreciation, a price on CO2 emissions, and net metering. In addition, I explore the effectiveness of feed-­‐in tariffs at mitigating the energy-­‐price risks to cogeneration projects.

In an effort to lower future CO2 emissions, a wide range of technologies are being developed to scrub CO2 from the flue gases of fossil fuel-based electric power and industrial plants. This thesis models two leading post-combustion CO2 capture technologies, a chilled ammonia-based CO2 capture process and an advanced amine-based CO2 capture process, and presents performance and cost estimates of these systems on pulverized coal and natural gas combined cycle power plants. The process modeling software package Aspen Plus® was used to develop performance and cost estimates for the chilled ammonia-based CO2 capture technology and general response surface equations were created for the model. Assumptions about plant financing and utilization, as well as uncertainties in cooling costs and chemical reaction rates that affect absorber cost were found to produce a wide range of cost estimates for ammonia-based CO2 capture systems. With uncertainties included, costs for a supercritical power plant with ammonia-based CO2 capture ranged from $80/MWh to $160/MWh, with the 95% confidence interval ranging from $95/MWh to $143/MWh (with all costs in constant 2007 US dollars). For the advanced amine-based CO2 capture technology, an existing amine-based response surface model developed using Protreat® simulations was modified to match the performance and cost characteristics of a modern amine-based system. The response surface models of both technologies were incorporated into the Integrated Environmental Control Model for use in developing performance and cost estimates of pulverized coal and natural gas combined cycle power plants with these technologies. The baseline costs for a supercritical power plant with advanced amine-based CO2 capture was $105/MWh and for the natural gas combined cycle power plant with advanced amine-based CO2 capture was $85/MWh. Both post-combustion CO2 capture technologies are then compared in terms of performance and cost for different ranges of fuel type, fuel cost, plant size, and CO2 capture system train size. A probabilistic cost difference analysis is also used to compare these technologies. The aminebased CO2 capture system is found to have a higher revenue requirement in all the case studies and only a 2% chance of having a lower revenue requirement than the advanced amine system in the probabilistic cost difference. Combined, these results suggest that the advanced amine system will have a cost advantage over the ammonia system in most cases, in the absence of significant new improvements in the ammonia system design. Finally, the importance of these estimates for policy makers is discussed.

Typewritten MS. / The theory of the propagation on electromagnetic waves through an ionized medium was given as early as 1909 by h. a. Lorentz in his famous book "Theory of Electrons". Many authors, notably Sir E. V. Appleton, immediately applied this theory to the study of the transmission of radio waves in the ionosphere, the existence of which was first suggested independently by Ke3nnelly and Heaviside in 1902. The numerous experimental data on short wave transmission accumulated in the past four decades have presented strong support to this theory. [...]

Note: / The minimization of slag entrainment during the liquid metal transfer•operations inherent to the continuous casting of steel is known to result inenhanced metal cleanness. Measures currently available to combat suchentrainment entail considerable loss of yield of liquid, as well as cast, steel. Slagvortexing is considered a major source of such entrainment. Slag entraining funnelformation, under vortexing as well as non-vortexing conditions, in water ladleswere studied. The role of a supernatant layer of oil was also addressed. Otherparameters in the study included the diameter of the ladle and nozzle, the initialliquid head of water in the ladle, and the length, entrance geometry, dischargecoefficient and eccentricity of the nozzle.[...] / Il est bien connu que la réduction de l'entrainement de laitier pendant les operations de transfert de métal liquide inherent a la coulée continue d'acier améliore la propreté du métal. Les méthodes disponibles actuellement pour combattre cet entrainement occasionnent des pertes d'acier, a l'état liquide ou coulé. Le vortex est considéré comme une source majeure d'entrainement de laitier. La formation d'entonnoir d'entrainement de laitier en presence ou non de vortex a été etudiée et le role d'une couche supérieure d'huile a aussi été considéré. Les autres parametres indus dans cette étude sont Ie diamètre de la poche et du trou de coulée, le niveau d'eau initial dans la poche, ainsi que la longueur, la géométrie d'entrée, le coefficient de décharge et l'excentricité du trou de coulée.