Thesis (Ph. D.)--University of California, 1924. / Originally issued by McGraw-Hill book company, inc., without thesis note. This edition is identical except for the addition of the thesis t.p.

Thesis (M.S.)--University of Wisconsin--Madison, 1961. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 95).

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 82-89). Also available on the Internet.

Adoption of smart mobile devices (smartphones, wearables, etc.) is rapidly growing. There are already over 2 billion smartphone users worldwide [1] and the percentage of smartphone users is expected to be over 50% in the next five years [2]. These devices feature rich sensing capabilities which allow inferences about mobile device user’s surroundings and behavior. Multiple and diverse sensors common on such mobile devices facilitate observing the environment from different perspectives, which helps to increase robustness of inferences and enables more complex context detection tasks. Though a larger number of sensing modalities can be beneficial for more accurate and wider mobile context detection, integrating these sensor streams is non-trivial. This thesis presents how multimodal sensor data can be integrated to facilitate ro- bust and energy efficient mobile context detection, considering three important and challenging detection tasks: indoor localization, indoor-outdoor detection and human activity recognition. This thesis presents three methods for multimodal sensor inte- gration, each applied for a different type of context detection task considered in this thesis. These are gradually decreasing in design complexity, starting with a solution based on an engineering approach decomposing context detection to simpler tasks and integrating these with a particle filter for indoor localization. This is followed by man- ual extraction of features from different sensors and using an adaptive machine learn- ing technique called semi-supervised learning for indoor-outdoor detection. Finally, a method using deep neural networks capable of extracting non-intuitive features di- rectly from raw sensor data is used for human activity recognition; this method also provides higher degree of generalization to other context detection tasks. Energy efficiency is an important consideration in general for battery powered mo- bile devices and context detection is no exception. In the various context detection tasks and solutions presented in this thesis, particular attention is paid to this issue by relying largely on sensors that consume low energy and on lightweight computations. Overall, the solutions presented improve on the state of the art in terms of accuracy and robustness while keeping the energy consumption low, making them practical for use on mobile devices.

Master of Science / Department of Biological & Agricultural Engineering / Ajay Sharda / In the agriculture industry, in-field efficiency of tractors is critical information for operators and producers. Properly matching tractor to implement using real-world tractor performance characteristics is the primary factor that effects in-field efficiency. Currently, tractor testing is primarily conducted in a controlled lab environment to quantify attributes such as power take-off (PTO) power and fuel consumption. However, in-field quantification of these attributes is necessary to gain a full understanding of the machine’s performance. Therefore, this study was conducted with two primary objectives: 1) develop a data acquisition system to measure real-time tractor performance at varying machine states during field operations, and; 2) evaluate the performance of tractors individually and compared to each other. Studies were conducted to test multiple different sized tractors with varying implements used in a specific crop production cycle; these tractors included two smaller 71 HP machines, a 90 HP and a 100 HP machine. The primary performance comparison goals were to evaluate the performance efficiency differences between a cabin and open station machine of the same size, and to evaluate the differences in performance between two similarly sized machines. A custom data acquisition (DAQ) system developed comprises of a torque sensor, flow meter, and GPS to acquire target performance parameters using a National Instruments cRIO system. The PTO torque sensor and fuel flow meter were tested and validated in a controlled lab using a PTO dynamometer and fuel scale. Validation field studies conducted showed that the DAQ system captured real-time performance parameters; strong correlation was observed between power, speed, and fuel consumption.   Using the real-time data allows for a better understanding of the relationship between machine and implement, as well as a more thorough understanding of the effect of terrain and crop load on fuel consumption and PTO power. The peak torque values through the implement drivetrain and their frequencies coupled with the average breakdown of power consumption by the implement gives the manufacturer and producer the opportunity to modify usage trends or design, respectively. Spatial fuel consumption data on a tractor by tractor basis allows varying machines to be compared directly based on their efficiency. Testing of the two smaller tractors took place on the same day in a uniform field. While the data did not indicate any difference between open station and cabin machines, strong correlation was observed between both operating speed and PTO mode selection and performance efficiency. The testing of the two larger tractors was done on sequential cuts of alfalfa on the same field; to account for this, bales were geotagged and weighed to produce a forage density map. Data from testing yielded two main results; the first being that the fuel consumption rate of each tractor and operation can be accurately predicted using an equation using PTO power and operating speed as variables. The equation that defines the fuel consumption for the swathing operation predicts the fuel consumption within 10% over 75% of the time in both sized machines. Data recorded by the DAQ system yields the information necessary to give the manufacturer a thorough understanding of how machines and implements interact with each other, as well as how external factors effect machine performance.

The act of dust sampling to characterise potential hazards in the respiratory tract is a process that requires initial removal of non-inspirable particles followed by separation into regional fractions. Particles that are not inhaled cannot deposit anywhere in the respiratory system. Furthermore, there is an important category of aerosol for which the conditions for potential injury is inhalation and deposition anywhere in the respiratory tract. Thus inspirable dust sampling is fundamental to all aerosol sampling for health risk evaluation. A proper estimation of inhalation exposure will need to examine the relationship between the inspiration efficiency of a sampler and particle size distribution of a dust cloud; and methods to collect a representative sample in the workplace.

Stag Hill is an example of a slope failure in London Clay. In 1964 it was proposed to develop the area, so the slope was stabilized using a drainage system and heavy buildings were constructed on piled foundations. Piezometers were also installed to establish the pore pressure pattern. In 1985 a general evaluation of the history of the failure, stabilization and development of the area was undertaken. This gave rise to the view that this area would be a very suitable place to establish a system for studying the efficiency of drainage systems. The presence of the drainage system, which initiates rapid fluctuation of ground water pressure in response to infiltration, brought about the necessity of attention to the errors associated with time lag which would be involved in monitoring of pore water pressure. Later on, when the ground water pressure was being monitored, it was observed that changes of atmospheric pressure significantly affects the records of vibrating wire piezometers. In this way the necessity of the evaluation of difficulties and errors associated with atmospheric pressure in monitoring of ground water pressure automatically merged into the research. Accordingly, to fulfill the above mentioned aspects, all available piezometer records since 1964 were collected and plotted. All piezometers which survived were tested to see if they were still reliable. Drainage trenches were located at appropriate locations and over 60 new piezometers of different types were installed at different depths, in drained and non-drained areas, and in the trenches. Two types of pore water pressure measurements, daily and weekly, were taken. To record the duration and intensity of daily rainfall, an automatic tilting bucket system was installed in the area. To include the effect of the atmospheric pressure on the evaluation of the pore water pressure pattern, records of atmospheric pressure, taken at Gatwick airport were used. The main conclusions are that: Monitoring of ground water pressure, using stand pipe piezometers, in drained areas may lead to serious errors, say 1.0 meter head of water. Application of rigid piezometers is necessary but not enough, unless a reasonable correlation is established between piezometer reading times and rainfall periods. Changes of atmospheric pressure are a significant source of error in monitoring of ground water pressure techniques. A method to correct piezometer readings for changes in atmospheric pressure was established. At Stag Hill, the ground water pressure pattern, and in turn the stability of slopes is governed by layers of higher permeability in the range of 10[-5] - 10[-6] cm/sec. The main drainage system having a spacing to depth ratio of S/D = 3.4 - 3.8 has not efficiently improved the stability of the slopes. Surface covering (buildings and paving), however, has a dominant effect on the improvement of safety factor. At Wates House, the drainage system having S/D = 1.1, has lowered the ground water pressure with 92% efficiency. It takes some years before the ultimate efficiency of a drainage system takes effect. The efficiency of drainage trenches below invert level varies between the maximum and minimum efficiency of drains at invert level, in the long term. The theoretical methods for design of drainage trenches do not agree with practice. A practical design curve was suggested.

This thesis analyses the cost and profit efficiencies of the GCC banking sector over the period 1995-2000. Efficiencies are estimated using the most recent frontier technique, the Fourier Flexible form. The thesis also uses a logistic regression model to estimate the determinants of GCC banking efficiency. The findings show that the level of inefficiencies in the GCC banking industry ranges between 8 and 10% for costs, and 30 and 32 % for profits. There are no major differences in banks inefficiency levels among GCC countries. Moreover, inefficiencies show almost stable trends over 1995-2000. Comparisons of inefficiency levels across bank ownership type and assets size reveal that national banks are more cost efficient but less profit efficient than foreign banks. In terms of bank size, large banks are found to be more cost efficient but less profit efficient than other sized banks. The results also indicate that foreign banks have on average been operating with higher scale diseconomies than national banks. Moreover, scale diseconomies decline as the assets sizes of both national and foreign banks increase. The main results from our logistic regression are that the strengthening of financial capital is a central element explaining bank efficiency in the GCC region; however, the erosion in loan quality reduces banking sector efficiency. The main policy conclusion from this thesis is that GCC governments need to continue to implement financial reform packages that strengthen banking system soundness, foster banking competition, and also devise incentive schemes to improve managerial efficiency in order that GCC banks are better placed to meet the challenges of greater openness.

Working fluids for thermal heat pump cycles have been studied. Methanol in conjunction with a mixture of inorganic bromides has been identified as being suitable for transforming heat from temperatures below zero centigrade. A computer programme was written in order to calculate the performance of such a combination, and its accuracy was verified by comparing its predictions with the actual performance of existing (commercial) heat pumps and chillers using combinations other than the above. Transport and other properties of the mixture have been measured, including vapour pressure, specific heat, viscosity, relative density, solubility, thermal conductivity, surface tension, heat of absorption, absorption coefficient, and hence mass diffusivity. An intermittent absorption heat pump was constructed and its performance measured. The tests demonstrated that it was capable of pumping heat from -10 °C up to 74 °C.