Traditional psychology has held the view that mentally healthy people have a good grasp of reality. However, studies on self-concept, perceived control and optimism have shown that mentally healthy people have a tendency to distort reality in these areas in a positive, self-serving direction. These studies led Shelley Taylor to coin the term "positive illusions" to describe overly positive self-evaluations, exaggerated perceptions of control, and unrealistic optimism. Taylor also theorized that those who were depressed had fewer positive illusions than those who were not depressed. The current study attempted to extend the foundation of basic research on the concept of positive illusions as well as their relationship to depression. Participants were given questionnaires at two time points (summer and winter) that measured the three components of positive illusions as well as Seasonal Affective Disorder (SAD), or winter depression. It was expected that those who had SAD would be depressed in the winter and therefore have fewer positive illusions at that time than in the summer when they were less depressed. Significant positive correlations between selfconcept, perceived control, and optimism indicated shared variance which is consistent with the existence of an underlying variable, i.e. positive illusions. Though results showed no difference in positive illusion scores between summer and winter, those with higher SAD scores (signifying greater depression) had fewer positive illusions at both time points than those with lower SAD scores. Finally, the remarkable similarity between positive illusion scores at the two time points suggests that positive illusions may exist as a personality trait, rather than being state dependent. Drawbacks of this study and suggestions for future research are discussed.

No description available.

Thesis (Ph.D.)--Boston University / This study was designed to investigate whether individuals with perennial rhinitis, a disorder conceived of as psychosomatic, would evidence fantasies either of maternal domination or of maternal rejection. It was hypothesized that: (1) Cases of perennial rhinitis evidence more intense fantasies of maternal domination than do cases of seasonal rhinitis or do symptom-free individuals; and (2) Cases of perennial rhinitis evidence no more intense fantasies of maternal rejection than do cases of seasonal rhinitis or normals. [TRUNCATED]

Wet-pavement friction is one of the most important pavement characteristics in relation to highway safety. This property is difficult to measure because it is affected by many vehicle, driver, pavement, and environmental parameters. In particular, it has been observed that both short- and long-term seasonal variations impact wet-pavement friction. Temperature, rainfall, and contaminants accumulated on the pavement surface affect the friction measurements. The objective of this thesis was to quantify the effect of seasonal variations on pavement surface friction measurements on hot-mix asphalt surfaces. Monthly measurements of friction and texture were collected on nine hot-mix asphalt sections at the Virginia Smart Road for a year and a half. Friction was measured using two locked-wheel trailers and a Dynamic Friction Tester. Measurements with the two types of equipment were conducted in the same day. Macrotexture measurements were taken using a Circular Texture Meter on the same locations used for the DFTester measurements. In order to compare friction measurements on the different surfaces, the monthly friction values were normalized by dividing the value obtained each month by the August 2007 measurements, which were theoretically the lowest friction numbers. The resulting ratios were considered friction correction factors to bring the friction measurements to the lowest value. After studying the friction variation throughout the year, sinusoidal models were fitted to the data to predict monthly correction factors for measurements at different speeds using both devices. The main conclusion of this investigation is that seasonal variation has a significant effect on pavement friction measurements. The general trend observed is that the measurements are higher in the winter months than in the summer months. This tendency follows a cyclical sinusoidal pattern throughout the year, similar to the air temperature variations. This suggested that temperature was at least one of the factors that affected the fiction correction factors. Better coefficients of determination were obtained for the DFTester models than for those for the locked-wheel devices. However, the sinusoidal model determined for the locked-wheel device at 64 kph (40 mph), which is the standard test velocity, fit relatively well the measured friction correction factors. Average friction correction factors for the Commonwealth of Virginia were proposed using these models. The study also showed that the friction correction factors are speed-dependent and are affected by the macrotexture of the pavement surface. The maximum (winter) friction correction factors were found to decrease with increased macrotexture for both devices at all speeds. The effect is more pronounced, however, for the locked-wheel measurements than for the DFTester measurements. / Master of Science

Thesis (M.A.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 167-178). Also available via the World Wide Web.

Thesis (doctoral)--Rijksuniversiteit te Utrecht, 1984. / Summary in English. Includes bibliographical references (p. 377-390) and index.

Thesis (doctoral)--Rijksuniversiteit te Utrecht, 1984. / Summary in English. Includes bibliographical references (p. 377-390) and index.

Typescript, etc.

Sodium balance and mortality rates were examined in five species of adult waterboatmen (Hemiptera: Corixidae) exposed to neutral and low pH waters. The five species were chosen to reflect a wide range of pH conditions in waters where they naturally occur. Cenocorixa bifida and C. expleta normally inhabit high pH waters, whereas C. blaisdelli and Hesperocorixa atopodonta can be found most often at neutral pH. Sigara omani occur in acidic waters. Haemolymph [Na], whole-body [Na], and sodium influx rates were recorded during exposures of 6-9 days at pH 7.0, 4.5, and 3.0. C. blaisdelli and H. atopodonta were studied throughout the year (spring, summer, and fall) . C. bifida and C. expleta were examined in the fall, while S. omani were tested in the spring. Overall, these corixids appeared to be tolerant of short-term exposure to low pH. Mortality for all species remained below 50% in both neutral and acidic pH levels throughout the year. Additionally, differences in haemolymph [Na], whole-body [Na], and sodium influx rates from pH 7.0 to either pH 4.5 or 3.0 were rarely significant. However, both inter- and intraspecific variation in sodium balance over the range of pH levels tested were apparent. Most notably, C. blaisdelli and H. atopodonta exhibited their highest concentrations of haemolymph and whole-body Na in the summer, under both natural conditions and in the laboratory at all pH levels. For C. blaisdelli, summer was also the time of highest mortality, with mortality increasing as pH was lowered. The observed correlation between high haemolymph/whole-body [Na] and high mortality in the summer appears to result from a relatively large decrease in haemolymph and whole-body [Na] when bugs were exposed to pH 3.0, at a time when these values were initially high. Fall was the season of lowest haemolymph/whole-body [Na], and also of lowest mortality, for both C. blaisdelli and H. atopodonta. Interspecific variation in the ability to tolerate low pH did not appear to reflect variation in the pH of water these bugs normally inhabit. Of the five species tested, H. atopodonta appeared best able to maintain internal homeostasis under acidic conditions, despite being common to neutral waters. Haemolymph [Na], whole-body [Na], and sodium influx rates did not change significantly from pH 7.0 to pH 3.0 in any season. Furthermore, C. blaisdelli, which was collected from the same pond as H. atopodonta, seemed to be least able to regulate internal milieu in low pH waters. In C. blaisdelli, exposure to pH 3.0 usually resulted in decreased haemolymph and whole-body [Na], relative to values recorded in those individuals exposed to pH 7.0. The difference in the size of these two species (H. atopodonta is approximately twice that of C. blaisdelli) may account for the observed variations in their respective sodium balance at low pH. / Science, Faculty of / Zoology, Department of / Graduate

Traffic volume data are input to many transportation analyses including planning, roadway design, pavement design, air quality, roadway maintenance, funding allocation, etc. Annual Average Daily Traffic (AADT) is one of the most often used measures of traffic volume. Acquiring the actual AADT data requires the collection of traffic counts continuously throughout a year, which is expensive, thus, can only be conducted at a very limited number of locations. Typically, AADTs are estimated by applying seasonal factors (SFs) to short-term counts collected at portable traffic monitoring sites (PTMSs). Statewide in Florida, the Florida Department of Transportation (FDOT) operates about 300 permanent traffic monitoring sites (TTMSs) to collect traffic counts at these sites continuously. TTMSs are first manually classified into different groups (known as seasonal factor categories) based on both engineering judgment and similarities in the traffic and roadway characteristics. A seasonal factor category is then assigned to each PTMS according to the site’s functional classification and geographical location. The SFs of the assigned category are then used to adjust traffic counts collected at PTMSs to estimate the final AADTs. This dissertation research aims to develop a more objective and data-driven method to improve the accuracy of SFs for adjusting PTMSs. A statewide investigation was first conducted to identify potential influential factors that contribute to seasonal fluctuations in traffic volumes in both urban and rural areas in Florida. The influential factors considered include roadway functional classification, demographic, socioeconomic, land use, etc. Based on these factors, a methodology was developed for assigning seasonal factors from one or more TTMSs to each PTMS. The assigned seasonal factors were validated with data from existing TTMSs. The results show that the average errors of the estimated seasonal factors are, on average, about 4 percent. Nearly 95 percent of the estimated monthly SFs contain errors of no more than 10 percent. It was concluded that the method could be applied to improve the accuracy in AADT estimation for both urban and rural areas in Florida.