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This study investigated a local aspect of theSwedish elementary school modernization process between the years 1871-1882.Previous studies have been drawn from the school inspectors own reports andshow that the schoolboards housed a negative and resentful attitude towardsreforms and the school inspectors often felt that the parish priests were moreinclined to changes than the schoolboards themselves.  Other research on elementary schoolmodernization has stressed the matching grants as a major cause of developmentand further establishment. In this study, however, a schoolboards own notes inthe form of meeting protocols during an eleven year period as well as a letterby a priest Erik Lundberg, Redogörelseför skolhusfrågan i Tierp dated 6 October 1880 were analyzed to see if theprevious explanation of school modernization, in particular with regard to thereluctance to change by the schoolboards goes to demonstrate and confirm. Theresults of this study have shown that even if the schoolboards do notimmediately follow the school inspectors instructions, it seems not primarilybeen due to resentment. Reforms within the school world are well known forbeing time-consuming but for the current period, as this study concerns andwithin this specific parish there were conflicts of interest which are notshown when only the inspector’s accounts and reports are examined. The late 1900thcentury was a time with a great deal of overwhelming and overthrowingreformations and changes witch challenged its previous social structuresthrough industrialization, urbanization and new political currents. Developmentand change occurs faster than news of it could travel, and it has been aninteresting journey to study these documents and to get a glimpse into how aschoolboard in a rural parish dealt with expansion and change.

Defects in Aluminum, Stainless steel and galvanized steel sheets are studied in reflection mode infrared thermography. The effect of material properties, surface finish, heating intensity, heater emission spectra, pixel size and defect size are studied. Contrast is governed by heat quality, emissivity and defect geometry—which follows a logarithmic trend. The diameter detected via infrared thermography is found to be at least 30% larger than the measured diameter and sub-pixel defects can be detected. The use of gradient and Laplacian of temperature is introduced as a means of increasing defect contrast and mitigating heater variation.

The US Navy spends around $75 million on maintenance and rework of corroded structures, especially in the ballast tanks of ships. The Navy will profit immensely with better surface coating and quality at source with real time inspection system. The approach taken to improve the coating is the use of optically active paint system. This kind of paint will fluoresce with an incident UV light. The fluorescence or glow can be used to detect holidays or defects on the surface. The inspection prototype developed uses a high end camera and intense UV light source. The paint and additive properties are characterized with the help of ultraviolet-visible spectroscopy (UV Vis) to study the behavior and to help formulate a theory. The holidays or missed spots in the painted surface will appear dark and non-fluorescing which is enhanced with the use of commercial filters.

The most urgent amphibian conservation issue in the Upper Midwest has been Blanchard's cricket frog (Acris crepitans blanchardi) declines over much of their northern range. Several causes have been proposed to explain these declines, including pesticide applications, disease, habitat loss, and habitat modification. My goal was to explore these proposed causes. Using a combination of field and laboratory analyses, including population analyses, gross inspections for malformations, and a histopathological analysis for indicators of fungus, disease and parasites, I found evidence for disease (a viral infection) and stress (fluctuating asymmetry, malformations and parasitism). Interestingly, the population most affected by these factors was also the one that contained the most animals and was located south of the presumed decline front (i.e., was assumed to be healthy). / Department of Biology

The maintenance of equipment has been an important issue for companies for many years. For systems with hidden or unrevealed failures (i.e., failures are not self-announcing), a common practice is to regularly inspect the system looking for such failures. Examples of these systems include protective devices, emergency devices, standby units, underwater devices etc. If no periodical inspection is scheduled, and a hidden failure has already occurred, severe consequences may result. Research on periodical inspection seeks to establish the optimal inspection interval (Failure Finding Interval) of systems to maximize availability and/or minimize expected cost. Research also focuses on important system parameters such as unavailability. Most research in this area considers non-negligible downtime due to repair/replacement but ignores the downtime caused by inspections. In many situations, however, inspection time is non-negligible. We address this gap by proposing an optimal failure finding interval (FFI) considering both non-negligible inspection time and repair/replacement time. A novel feature of this work is the development of models for both age-based and calendar-based inspection policies with random/constant inspection time and random/constant repair/replacement time. More specifically, we first study instantaneous availability for constant inspection and repair/replacement times. We start with the assumption of renewal of the system at each inspection. We then consider models with the assumption of renewal only after failure. We also develop limiting average availability models for random inspection and repair/replacement times, considering both age-based and calendar-based inspection policies. We optimize these availability models to obtain an optimal FFI in order to maximize the system’s availability. Finally, we develop several cost models for both age-based and calendar-based inspection policies with random inspection time and repair/replacement time. We formulate the model for constant inspection time and repair/replacement time as a special case. We investigate the optimization of cost models for each case to obtain optimal FFI in order to minimize the expected cost. The numerical examples and case study presented in the dissertation demonstrate the importance of considering non-negligible downtime due to inspection.

The maintenance of equipment has been an important issue for companies for many years. For systems with hidden or unrevealed failures (i.e., failures are not self-announcing), a common practice is to regularly inspect the system looking for such failures. Examples of these systems include protective devices, emergency devices, standby units, underwater devices etc. If no periodical inspection is scheduled, and a hidden failure has already occurred, severe consequences may result. Research on periodical inspection seeks to establish the optimal inspection interval (Failure Finding Interval) of systems to maximize availability and/or minimize expected cost. Research also focuses on important system parameters such as unavailability. Most research in this area considers non-negligible downtime due to repair/replacement but ignores the downtime caused by inspections. In many situations, however, inspection time is non-negligible. We address this gap by proposing an optimal failure finding interval (FFI) considering both non-negligible inspection time and repair/replacement time. A novel feature of this work is the development of models for both age-based and calendar-based inspection policies with random/constant inspection time and random/constant repair/replacement time. More specifically, we first study instantaneous availability for constant inspection and repair/replacement times. We start with the assumption of renewal of the system at each inspection. We then consider models with the assumption of renewal only after failure. We also develop limiting average availability models for random inspection and repair/replacement times, considering both age-based and calendar-based inspection policies. We optimize these availability models to obtain an optimal FFI in order to maximize the system’s availability. Finally, we develop several cost models for both age-based and calendar-based inspection policies with random inspection time and repair/replacement time. We formulate the model for constant inspection time and repair/replacement time as a special case. We investigate the optimization of cost models for each case to obtain optimal FFI in order to minimize the expected cost. The numerical examples and case study presented in the dissertation demonstrate the importance of considering non-negligible downtime due to inspection.

Resistance spot welding is used frequently as a successful joining method for a variety of work commonly in automotive and other manufacturing processes. Spot weld nugget is generally hidden between two sheets, causing its inspection difficult and expensive. Undersized nuggets, brittle or cracked nuggets, and excessive indentation of electrodes reveals the lack of fusion between the parts that can make the weld sub-standard. Visual inspection, pry testing and physical teardown with chisel and hammer method or a combination of them are being used traditionally. However, this study presents a more effective nondestructive inspection method based upon an ultrasonic pulse-echo technique. The theory of the technique together with the experimental verification are presented and its advantages over the other destructive and nondestructive techniques are considered.

Thesis (M.P.H.)--University of Nevada, Reno, 2006. / "May 2006." Includes bibliographical references (leaves 83-87). Online version available on the World Wide Web.