1,720,999 research outputs found
Design of a flowrate measurement system for low-pressure gases
No full textDesign of a flow meter to be used in a low-pressure environment is hereafter presented. The need of this activity comes from the lack of commercial flow meters operating at low pressures due to the unusual working environment, where outgassing and sublimation phenomena becomes relevant for many materials and rarefied atmosphere changes dramatically the heat and mass exchange phenomena. In our case, the need of a low pressure compatible measurement system comes from the need of measuring the flow rate of a rotary vane pump working under an environmental pressure between 10 and 6 mbar, simulating the condition of the Martian atmosphere at the surface. The pump will be the key component of a particle analyzer that should be part of the ExoMars 2020 ESA-Roscosmos mission. The designed measurement system is based on the deformation of a control volume, a stainless-steel bellow, which has been designed on the basis of the expected flow rate. The measurement system has been calibrated at ambient condition and testing in low-pressure has been performed in order to validate the measurement method and derive the flow rate performances within the expected working conditions
Smart Solar Panel Project: Modelling of the Self-Cleaning Strategy by Piezoelectric Patches
No full textPhotovoltaic solar panels play a crucial role in energy generation in space. The Smart Solar Panel (SSP) project targets increasing the performance of such technology, developing PV (photovoltaic) panels with sun-tracking and selfcleaning capabilities for dusty applications. In this work, a numerical model to simulate the interaction between the piezoelectric patch and the panel is developed, allowing for the retrieval of the acceleration field generated at the panel's surface; then, a methodology to rank different configurations in terms of number, position and actuation characteristics of the actuators is introduced, enabling the identification of the optimal configuration to be adopted for the cleaning, keeping fixed the energetic input into the system
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Preliminary design of the inlet duct of a dust analyzer for Mars
Full text linkAirborne dust characterization is very important in planetary climatology, especially on Mars, where dust is always present and its concentration varies with seasons. This work deals with the design of the inlet duct of an instrument named MicroMED, devoted to characterize Martian dust but suitable to be mounted on different planetary landers or rovers. An inertial classifier has been developed to cut particles with diameter larger than 20 μm in order to avoid obstruction of the pumping system of the instrument. CFD simulations based on the Eulerian-Lagrangian approach were performed to characterize the separation performance of the classifier. Finally, the inlet duct has been mechanically designed by FE approach to assure resistance and proper mechanical behavior within expected mechanical environment
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
