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Er tong shui mian jie lü: zheng chang can kao zhi, xiang guan yin su, dui jian kang de ying xiang, he gan yu gai shan
No full textYu, Xinting.Thesis Ph.D. Chinese University of Hong Kong 2014.Includes bibliographical references (leaves 188-207).Abstracts also in Chinese; appendixes in Chinese.Title from PDF title page (viewed on 14, September, 2016).Yu, Xinting
Data associated with publication “Where does Titan Sand Come From: Insight from Mechanical Properties of Titan Sand Candidates”
No full textThe data files include original indentation data (load, depth, modulus, hardness) produced by a nanoindenter (Nanomechanics, Inc) for various Titan sand related materials, and AFM/SEM images of the indented cracks of some of materials.
Extensive equatorial linear dunes exist on Titan, but the origin of the sand, which appears to be organic, is unknown. We used nanoindentation to study the mechanical properties of a few Titan sand candidates, several natural sands on Earth, and common materials used in the Titan Wind Tunnel, to understand the mobility of Titan sand. We measured the elastic modulus (E), hardness (H), and fracture toughness (Kc) of these materials. Tholin's elastic modulus (10.4+/-0.5 GPa) and hardness (0.53+/-0.03 GPa) are both an order of magnitude smaller than silicate sand, which is also smaller than the mechanically weak white gypsum sand. With a magnitude smaller fracture toughness (Kc=0.036+/-0.007 MPa-m^(1/2)), tholin is also much more brittle than silicate sand. This indicates that sand formation mechanisms that require liquid hydrocarbons must be possible in the equatorial regions or sand formation does not require liquid, because tholin is too soft and brittle to transport from the poles, where the current lakes and seas are, to the equator.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
The Rheological and Thermal History of Kilauea's 2018 Fissure 17 Eruption
No full textKilauea's Fissure 17 eruption of 2018 was an anomaly among the other 24 fissures that erupted in the Lower Eastern Rift Zone in that it erupted explosively. Fissure 17 compositionally is an icelandite (an Fe-rich, Al-poor andesite) with highly crystalline mafic inclusions of an unknown origin. The presence of mafic inclusions in the icelandite indicates that mixing between at least two different magma bodies occurred prior to the eruption. The aim of this study is to understand why and how this fissure could have erupted explosively by attempting to identify the origins of the mafic inclusions. Two hypotheses were formulated for the origins of the inclusions, either (i) the mafic inclusions resulted from the injection of hot juvenile basaltic lava into the cooler icelandite, likely the same juvenile lava as was erupting from the dominant Fissure 8, , or (ii) the mafic inclusions are cold, brittle inclusions of wall rock (likely formed in 1955) that were mixed into the hotter icelandite. To test the hypotheses, crystallinity estimates for the icelandite (~64-80%), mafic inclusions (~68-91%), and 1955 lavas (~58-89%) were obtained via differential scanning calorimetry. MELTS modelling was utilized to test temperatures associated with the crystallinity and equilibrium temperatures associated with mixtures of 50:50, 60:40, and 70:30 mafic inclusions to icelandite. The observation of angular inclusions, and better match between the calculated and modeled crystallinity, suggest cold 1955 lava as the origin for the mafic inclusions, although with the current dataset we cannot disprove that Fissure 8 could be their source.Earth and Planetary Science
Spectral and Mineralogical Analysis of Planned CLPS Landing Sites with LRO-Lamp
No full textThis item is available only to currently enrolled UTSA students, faculty or staff. To download, navigate to Log In in the top right-hand corner of this screen, then select Log in with my UTSA ID.Before NASA's Artemis program brings humans back to the Moon, perhaps as early as 2025, many robotic missions will take place under the Commercial Lunar Payload Services (CLPS) initiative. Planned landing destinations include multiple areas of the South Pole and three enigmatic regions of interest: the Gruithuisen Domes, Reiner Gamma, and Mare Crisium. To aid in future CLPS surface measurements, we performed a series of analyses for each planned region using both remote sensing and sample analogs. Far-ultraviolet (FUV) remote sensing analysis was done with the Lyman Alpha Mapping Project (LAMP) instrument on the Lunar Reconnaissance Orbiter (LRO). For the South Pole, we analyzed dayside LAMP products, as an addition to previously studied nightside maps. For the more equatorial sites, we compared LAMP data with ultraviolet, visible, and near-infrared spectral observations from two previous lunar missions, Clementine and Kaguya. The Gruithuisen Domes and Reiner Gamma both exhibit high FUV albedo ratios, likely correlated to high quantities of feldspathic minerals or less space weathering, respectively. Mare Crisium, however, is more uniform in the FUV, with only some differences in albedo ratio occurring between inside the basin and outside the ring that encloses it. We compared the Gruithuisen Domes and Reiner Gamma to Apollo samples bearing mineralogical and regional similarities. The remote sensing data for Mare Crisium was compared directly to a return sample from the Luna 24 mission to this region. We identified unique spectral and mineralogical features at each CLPS site to aid in mission planning and future measurement interpretation.Physics and Astronom
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