1,721,091 research outputs found
Students' Educational Goals in Natural Language
No full textWe built this dataset is on 2.262 student goals in natural language, collected at the Universities of Bremen, Hannover, and Osnabrück in 2019. Six independent raters assigned tags from a set of 28 to those goals. The dataset includes the complete data processing pipeline, from raw data to results and figures generated by a data analysis script written in Python. The README.md file describes folders, files, and processing
Hierarchical Goal System Diagram Comparison
No full textThe data in this set stems from online studies in which students generated hierarchical goals systems (HGS) in two
online studies, and compared four types of visualizations for HGS. The technical setup consisted of a Django web application, publicly available under MIT license at
GitHub: https://github.com/fweber/GoalTree
Expansion-deflection nozzle design and performance optimization for upper-stage applications
Full text linkED nozzles have been studied for many years as a possible replacement for conventional rocket nozzles. For moderate nozzle pressure ratios, ED nozzles suffer from overexpansion losses and aspiration drag, making them inferior to plug nozzles and even dual bell nozzles. In high-altitude operation, ED nozzles show advantages over conventional nozzles due to lower divergence losses and, thus, possibly shorter design lengths promising higher performance-to-weight ratios as the plug nozzle. However, in contrast to plug nozzles, they feature less radial throat distances from the symmetry axis, reducing the wall surface exposed to the peak heat flux and thus the needed heat pick up from the cooling system. All these combined make the ED nozzle a promising concept for the upper stages. The ED nozzles in this work are designed with a dedicated design methodology that calculates the ideal contour, providing isentropic expansion. The supersonic walls are calculated using an approximate contouring method based on the MOC, which is integrated into different design procedures to find the desired nozzle iteratively. The design of the subsonic walls is kept as simple as possible, using only straight lines and arcs. Then, a VINCI - sized upper-stage Baseline ED and a conventional nozzle are designed, and preliminary CFD simulations are conducted to select suitable meshes for the parametric analyses. The parametric analyses investigate the influence of various geometrical parameters on the performance. The geometrical parameters are the outer nozzle dimensions, i. e. the truncation length and radius, the specific heat ratio design value, the radial throat shifting, the throat wall curvature radii, and the geometrical scaling factor. The CFD methods are verified and validated using the two conventional test case engines RL10A-3-3A and the SSME, providing less and more thrust than the VINCI reference engine
Siddata Study Assistant Dataset from Prototpye 2.0
No full textWe collected these data from user interaction with version 2.0 of the SIDDATA study assistant software. Students from three German universities used the software, and the dataset contains data from all three universities, only from those students who explicitly agreed to donate their data. Data aggregation occurred over the course of 11 months, from December 2020 to November 2021.
The dataset consists of one .csv file with 41.520 rows representing one activity. The semantics and the context of data acquisition are described in detail in the related publication
Siddata Study Assistant Dataset from Prototpye 3.0
No full textWe collected these data from user interaction with version 3.0 of the SIDDATA study assistant software. Students from three German universities used the software, and the dataset contains data from all three universities, only from those students who explicitly agreed to donate their data. Data aggregation occurred over the course of 5 months, from December 2021 to May 2022. The dataset consists of one .csv file with 21.890 rows representing one activity. The semantics and the context of data acquisition are described in detail in a related publication. https://doi.org/10.5220/001103880000318
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
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
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