Composition of fine and ultra-fine particles and source identification by stable isotope ratios

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1998.Includes bibliographical references (leaves 117-124).by Jec-Kong Gone.Ph.D

Landslides on Ceres: Diversity and Geologic Context.

Landslides are among the most widespread geologic features on Ceres. Using data from Dawn's Framing Camera, landslides were previously classified based upon geomorphologic characteristics into one of three archetypal categories, Type 1(T1), Type 2 (T2), and Type 3 (T3). Due to their geologic context, variation in age, and physical characteristics, most landslides on Ceres are, however, intermediate in their morphology and physical properties between the archetypes of each landslide class. Here we describe the varied morphology of individual intermediate landslides, identify geologic controls that contribute to this variation, and provide first-order quantification of the physical properties of the continuum of Ceres's surface flows. These intermediate flows appear in varied settings and show a range of characteristics, including those found at contacts between craters, those having multiple trunks or lobes; showing characteristics of both T2 and T3 landslides; material slumping on crater rims; very small, ejecta-like flows; and those appearing inside of catenae. We suggest that while their morphologies can vary, the distribution and mechanical properties of intermediate landslides do not differ significantly from that of archetypal landslides, confirming a link between landslides and subsurface ice. We also find that most intermediate landslides are similar to Type 2 landslides and formed by shallow failure. Clusters of these features suggest ice enhancement near Juling, Kupalo and Urvara craters. Since the majority of Ceres's landslides fall in the intermediate landslide category, placing their attributes in context contributes to a better understanding of Ceres's shallow subsurface and the nature of ground ice

Os Backpackers: a importância do WOM e os seus antecedentes

Mestrado em Marketing ResearchO presente estudo analisa os factores antecedentes do conteúdo da mensagem Word-of-Mouth (WOM) dos backpackers. Propõe-se um modelo no qual o sentimento de pertença à comunidade backpacker é um constructo mediador essencial entre as motivações de viagem e o conteúdo da mensagem WOM. O modelo é testado empiricamente através de um inquérito a 656 backpackers de 75 países e utilizando um modelo de equações estruturais. Os resultados indicam que a motivação para viajar, os locais onde se dão as interacções sociais, o sentimento de pertença e as actividades culturais realizadas pelos backpackers influenciam o desenvolvimento do conteúdo da mensagem WOM. Implicações teóricas, de gestão e do ponto de vista do marketing são discutidas. Também são apresentadas direcções para futuras pesquisas.ABSTRACT: This study examines the antecedents of content of the message Word-of-Mouth (WOM) of backpackers. We propose a model in which the sense of belonging to the community is a key mediating constructs between travel motivations and content of the message WOM. The model is empirically examined by means of a survey conducted of 656 backpackers from 75 different countries and we use structural equation modeling The results indicate that travel motivation, sense of belonging, the place where social interaction occurs and the cultural activities undertaken by backpackers are an important antecedent of the content of Word-of-Mouth. Theoretical, managerial and marketing implications of Word-of-Mouth are discussed. Directions for future research are also presented