A study of the feasibility of using sea and wind information from the ERS-1 satellite. Part 1: Wind scatterometer data

The use of scatterometer and altimeter data in wind and wave assimilation, and the benefits this offers for quality assurance and validation of ERS-1 data were examined. Real time use of ERS-1 data was simulated through assimilation of Seasat scatterometer data. The potential for quality assurance and validation is demonstrated by documenting a series of substantial problems with the scatterometer data, which are known but took years to establish, or are new. A data impact study, and an analysis of the performance of ambiguity removal algorithms on real and simulated data were conducted. The impact of the data on analyses and forecasts is large in the Southern Hemisphere, generally small in the Northern Hemisphere, and occasionally large in the Tropics. Tests with simulated data give more optimistic results than tests with real data. Errors in ambiguity removal results occur in clusters. The probabilities which can be calculated for the ambiguous wind directions on ERS-1 contain more information than is given by a simple ranking of the directions

Understanding the Impact of Bead Type on Paint and Thermoplastic Pavement Markings

Each year the United States spends approximately two billion dollars maintaining pavement markings. In addition, an impending Federal policy establishing a minimum retro-reflectivity value for pavement markings has driven asset managers to develop performance models to effectively and efficiently manage these high quantity, low cost assets. Research over the past decade has sought to identify and understand the many factors influencing pavement marking degradation. Despite the fact that reflective glass beads are foundational to pavement marking retro-reflectivity, little research has specifically considered the impacts of bead type. The purpose of this study is to quantify the impact that bead type has on the degradation rate of waterborne paint and thermoplastic pavement markings in North Carolina. The results of an average value analysis and Wilcoxon rank sum test support the inclusion of bead type as a significant variable in future degradation models and the following two key findings. First, there is a statistically significant difference in the rate of retro-reflectivity degradation between standard beads and large beads for both thermoplastic and waterborne paint pavement markings. Second, thermoplastic pavement markings with standard beads are more economical than those with large beads in areas that experience snow plow operations

Modelling rhizomania in sugar beet

With love and gratitude to my parents, for all their advice and encouragement. Acknowledgements I would like to express my sincere gratitude to Dr. Fowler, for his help and guidance as my supervisor for this dissertation. I would also like to thank Dr. Howison for his support as my supervisor during the earlier part of the year, and Dr. Gilligan and Dr. Truscott for the invaluable discussions. I would like to thank the OCIAM Industrial Fund for funding me this year, and Lincoln College for the delicious food and comfortable accom-modation. My thanks go to Keith Gillow, who has always been helpful with queries about LATEX, and all the sta in the Mathematical Institute and Comput-ing Laboratory. I am very grateful to my parents and brother for their continuing guidanc

Binary Colloidal Alloy Test-5: Aspheres

The Binary Colloidal Alloy Test - 5: Aspheres (BCAT-5-Aspheres) experiment photographs initially randomized colloidal samples (tiny nanoscale spheres suspended in liquid) in microgravity to determine their resulting structure over time. BCAT-5-Aspheres will study the properties of concentrated systems of small particles when they are identical, but not spherical in microgravity.

Get a GRIP on Comprehension

Durkin\u27s research (1978-79) has indicated that much more time is spent testing reading comprehension than teaching it. Consequently, all reading comprehension skills need to be taught by the teacher to the students in the classroom. Since making inferences is a necessary comprehension skill when reading across the curriculum (Gordon, 1985), it also must be taught. However, many children find it difficult to make inferences because they are required not only to derive a conclusion from the facts or premises found in their reading materials, but in many cases, they must go beyond the text to their own knowledge and experiences for information. Thus, prior knowledge which student bring to the text, as well as their sensitivity to the text information, are essential aspects of inferential comprehension