1,720,958 research outputs found
Hands-on education for innovative research fields: A cubesat manufactured with rapid protyping technique
No full textThe structure of Cubesat that will be presented in the following paper was realized within the activities of Space Robotics Laboratory (SRL) and the V-Lab of the II Faculty of Engineering of Bologna University in collaboration with the Space System group of University of Rome "LA SAPIENZA". The work team that is persecuting the project proposed is composed by PHD, master and bachelor students. Several projects aimed at hands-on education are developed by the SRL including: an observatory for observation and monitoring of space debris and the creation of payloads for sounding rockets and stratospheric balloons, that are part of the ESA education program; together with the realization of the Cubesat depicted in the paper. Cubesat is a cube-shaped nano-satellite with the side of 100 mm. Despite its small size, it has a system for attitude control, a telecommunication system, a camera and a power system. Considering the size and requirements of the various systems, the organization of interior spaces was one of the major issues in the design of the structure for which it was necessary to identify innovative solutions. The Cubesat structure was realized by polymer (ABS - Acrylonitrile - Butadiene - Styrene) with the technique of "rapid prototyping" thanks to equipment provided by the V-Lab of the II Faculty of Engineering of University of Bologna. The Rapid Prototyping technique has several advantages including the quick implementation and low cost. Moreover, for the construction of a small satellite it is very useful the ability to succeed in details, sometimes difficult to achieve with the use of tools machine except with a significant increase in costs. Another important advantage is the ability to use a material with a lower density than the commonly used aluminum alloy. The structure must be able to resist at the stresses due to the launch vibrational and static loads. For this several simulations using a FEM code have been performed during the design phase, moreover a Test-Pod system in aluminum alloy was built and used to perform vibration tests for the qualification to launch with Indian PLSV launcher of the Cubesat prototype. The paper shows the detailed design of the Cubesat with the analysis of solutions to the critical points, the results of numerical simulations and the results of vibration tests carried out for the launch qualify on the Cubesat prototype. Copyright ©2010 by the International Astronautical Federation. All rights reserved
Hands-on education for innovative research fields: a cubesat manufactured with rapid protyping technique
No full textThe structure of Cubesat that will be presented in the following paper was realized within the activities of Space Robotics Laboratory (SRL) and the V-Lab of the II Faculty of Engineering of Bologna University in collaboration with the Space System group of University of Rome “LA SAPIENZA”. The work team that is persecuting the project proposed is composed by PHD, master and bachelor students
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
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
Redemption: A student experiment proposing a solution to Active Debris Removal
No full textREDEMPTION (REmoval of Debris using Material with Phase Transition: IONospherical tests) is a student experiment aiming to propose a feasible solution for Active Debris Removal. Completely con-ceived, designed and realised within the Space Robotic Laboratory (SRL) of the II Faculty of Engineering of the University of Bologna "ALMA MATER STUDIORUM", REDEMPTION has been selected to participate to REXUS/BEXUS 2012 Programme. This programme is realised under a bilateral Agency Agreement between the German Aerospace Center (DLR) and the Swedish National Space Board (SNSB). The Swedish share of the payload has been made available to students from other European countries through a collaboration with the European Space Agency (ESA). The REDEMPTION experiment base-concept seems up-to-date, as at the moment space debris problem is one of the most challenging space research fields: at the moment the situation of debris population is quite critical, because every new collision produces in its turn other satellite fragments, increasing the total number of debris and the probability of new impacts (the so-called Kessler-Syndrome). Due to the complexity of the task, no feasible solution has been found so far. One of the most critical aspects to be solved in debris removal missions, is how to connect the debris to be removed to the cleaner satellite. On this matter, through REDEMPTION experiment students aim to evaluate the feasibility of an ADR system based on a polyurethanic foam. The foam under evaluation is generated starting from two liquid reagents, that need to be mixed to produce a polymeric structure, that after a short time becomes solid and rigid. The opportunity to launch the experiment on board the REXUS rocket allows to verify the behaviour of the foam in near space conditions, that is milli-gravity and vacuum conditions. In this paper the educational aspects of the project is depicted, as well as the technical details regarding the three sub-experiments which constitute the REDEMPTION module. Moreover, the results of the launch campaign will be discussed, drawing the conclusions of the project
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