Archaeology from Space: Advanced Satellite Imagery Through the Work of Sarah Parcak

The ancient past and the technological future come together in “space archaeology.” Focusing on the colorful career of Sarah Parcak, this article shows how advanced satellite imagery is being used to discover new archaeological sites—as well as to monitor existing ones at a time when looting is on the rise

One and a half century of diffusion: Fick, Einstein before and beyond

The year 2005 gave us, through two anniversaries (1855 Fick and 1905 Einstein), the wish to go back to these authors’ seminal papers, whose aftermath had been (and still is) prodigious. This essay describes the contents of these articles: the macroscopic approach with Fick equations and the microscopic one with the Einstein-Smoluchowski random walk (Brownian motion) equation, while considering them in their historical context. Some further developments are briefly discussed

Alien Registration- Dion, Philibert (Lewiston, Androscoggin County)

https://digitalmaine.com/alien_docs/29688/thumbnail.jp

A VISION-BASED QUALITY INSPECTION SYSTEM FOR FABRIC DEFECT DETECTION AND CLASSIFICATION

Published ThesisQuality inspection of textile products is an important issue for fabric manufacturers. It is desirable to produce the highest quality goods in the shortest amount of time possible. Fabric faults or defects are responsible for nearly 85% of the defects found by the garment industry. Manufacturers recover only 45 to 65% of their profits from second or off-quality goods. There is a need for reliable automated woven fabric inspection methods in the textile industry. Numerous methods have been proposed for detecting defects in textile. The methods are generally grouped into three main categories according to the techniques they use for texture feature extraction, namely statistical approaches, spectral approaches and model-based approaches. In this thesis, we study one method from each category and propose their combinations in order to get improved fabric defect detection and classification accuracy. The three chosen methods are the grey level co-occurrence matrix (GLCM) from the statistical category, the wavelet transform from the spectral category and the Markov random field (MRF) from the model-based category. We identify the most effective texture features for each of those methods and for different fabric types in order to combine them. Using GLCM, we identify the optimal number of features, the optimal quantisation level of the original image and the optimal intersample distance to use. We identify the optimal GLCM features for different types of fabrics and for three different classifiers. Using the wavelet transform, we compare the defect detection and classification performance of features derived from the undecimated discrete wavelet and those derived from the dual-tree complex wavelet transform. We identify the best features for different types of fabrics. Using the Markov random field, we study the performance for fabric defect detection and classification of features derived from different models of Gaussian Markov random fields of order from 1 through 9. For each fabric type we identify the best model order. Finally, we propose three combination schemes of the best features identified from the three methods and study their fabric detection and classification performance. They lead generally to improved performance as compared to the individual methods, but two of them need further improvement

Thermoluminescence of Zircon

The thermoluminescence (TL) of synthetic zircons into which some impurities have been individually insert-ed is investigated. The results obtained show that, after X-irradiation at 77K, the synthetic zircons present three kinds of thermoluminescent emissions. The first is related to the OH- ions, the second is typical of the SiO44-groups, and the third is characteristic of RE3+ ions with RE = Dy, Tb, Gd, Eu, or Sm (RE = rare earth). The OH- emission is a large band at 285 nm which appears at 115 and 160K. The SiO44- TL emission consists of a 365 nm band observed at 100, 165, 205, 260, and 325K. The mechanisms associated with these TL peaks are fairly well described in terms of an electron trapped in the field of two positive charges, one substituted to silicon ion, the other to a neighbouring oxygen ion. For temperatures up to 350K, the characteristic emissions of RE3+ are the consequence of an energy transfer mechanism from the TL emission as a result of recombination in SiO44- host groups or OH- centres to the RE3+ emitting activators. At temperatures higher than 350K, there are also some other RE3+ characteristic peaks which are interpreted in terms of charge transfer mechanisms. The systematic compilation of results obtained with a series of natural zircons from various origins shows that the main TL properties are explained by the mechanisms described above