1,721,035 research outputs found
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
Probabilistische basierte Topology Optimization in ANSYS
Full text linkOptimization is a process or methodology of making something as fully perfect, functional or effective as possible. Structural optimization in the thesis focuses on optimal design of the loaded structures. The optimal topology design which is a type of structural optimization is defined as optimization problem of material distribution. The material densities of finite elements serve as variables and the maximum stiffness is defined as objective function. The interest for finding optimal design grows in recent years because it gives us a possibility to save the material that doesnt significantly contributes in the global stiffness of the structure. Probabilistic design is widespread discipline in engineering. It considers uncertainties in the structures. These uncertainties and random effects are related to quality and reliability of the structure. Probabilistic design is not used very often in the civil engineering because engineers rely on prescribed building codes and safety factors. In recent years there has been a growing interest to combine probabilistic design with topology optimization. Techniques for combining these two analyses presented to this day are very time consuming and therefore expensive. They are also unreachable to every engineer. In this work a simplified method for engineers is presented. It combines the deterministic load cases that came from probabilistic analysis into an end topological solution. Monte Carlo simulation is applied for the probabilistic analysis.Optimization is a process or methodology of making something as fully perfect, functional or effective as possible. Structural optimization in the thesis focuses on optimal design of the loaded structures. The optimal topology design which is a type of structural optimization is defined as optimization problem of material distribution. The material densities of finite elements serve as variables and the maximum stiffness is defined as objective function. The interest for finding optimal design grows in recent years because it gives us a possibility to save the material that doesnt significantly contributes in the global stiffness of the structure. Probabilistic design is widespread discipline in engineering. It considers uncertainties in the structures. These uncertainties and random effects are related to quality and reliability of the structure. Probabilistic design is not used very often in the civil engineering because engineers rely on prescribed building codes and safety factors. In recent years there has been a growing interest to combine probabilistic design with topology optimization. Techniques for combining these two analyses presented to this day are very time consuming and therefore expensive. They are also unreachable to every engineer. In this work a simplified method for engineers is presented. It combines the deterministic load cases that came from probabilistic analysis into an end topological solution. Monte Carlo simulation is applied for the probabilistic analysis
Topological optimization of a dance floor
Full text linkIm Zuge dieser Diplomarbeit wird ein Tanzboden hinsichtlich seines durch klassisches Tanzen verursachten Schwingverhaltens untersucht und optimiert. Wegen der niedrigen Eigenfrequenz des Tanzbodens können durch Tanzen Schwingungen hervorgerufen werden, die die Gebrauchstauglichkeit reduzieren und eventuell Panik auslösen können. In Extremfällen kann es zum Versagen der Struktur kommen. Daher ist die Verbesserung des Schwingverhaltens notwendig und nützlich. Da der Entwurf des Tanzbodens Resonanz verhindern soll, wird eine Topologieoptimierung durchgeführt. Die Zielfunktion stellt die Maximierung der ersten Eigenfrequenz dar und als Randbedingung wird eine obere Grenze für das Volumen definiert. Die Hohlkörpertechnologie für Stahlbetondecken beschreibt die technologische Randbedingung des Optimierungsproblems. Aufgrund der Optimierungsergebnisse wird ein realisierbares Modell erstellt. Die Analyse jenes Modells zeigt, dass die Optimierung erfolgreich war, da die Durchbiegung abgenommen hat.The thesis deals with a dance floor analysis and optimization concerning its dynamic behavior caused by classical dancing. Due to its low eigenfrequency, dancing can cause vibration, which reduces the structural serviceability potentially leading to panic. In extreme cases the structure can collapse. Hence improving the vibration behavior of the dance floor is necessary and useful. Given that the design of the dance floor has to eliminate the danger of resonance, the design is defined as a topology optimization problem. The objective is the maximization of the first eigenfrequency and the constraint is defined as a maximum of the volume. The technology of composite reinforced concrete with polystyrene elements used for the floor prescribes the constraint by technology. Based on this optimization a realizable model is developed. The analysis of the designed structure shows, that the optimization of the dancing floor was successful as the deflection caused by classical dancing decreased
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
Ansätze zur Abschätzung von Verschiebungen einer Brücke aus gemessenen Beschleunigungsdaten
No full textThe progressive aging and deterioration of the health condition of bridges due to their usage raises concerns about their structural safety and usability. Regular inspections are conducted in order to assess the current condition of the structures, though certain types of sustained damages are difficult to detect with the primarily visual inspections. To address this issue, health monitoring systems consisting of various sensors attached to the structure are employed, providing additional information as a basis for decisions regarding appropriate maintenance measures. The monitoring system can be either permanent, operating under daily live load conditions, or temporarily applied during inspections. Especially in steel bridges, the knowledge of the displacement response enables the identification of dynamic deformations, which cause localised stress concentrations and can lead to fatigue and brittle damage. The displacement responses can be either obtained from the measurements of displacement sensors or determined by double integration of recorded acceleration data from the sensors of the monitoring system. As the former approach proves impractical in application, the integration of acceleration records to displacement responses seems a better choice. However, data obtained from acceleration sensors include measurement errors, which accumulate when integrated twice, leading to physically unlikely displacement shifts and distortions. The focus of this work lies on presenting and evaluating different approaches on the removal of the effect of measurement errors in the integration process, application of the selected methods on measured data and evaluating their applicability and the accuracy of the results. In the first part of this thesis, an introduction to structural health monitoring is given and the basic theory and difficulties in the integration procedure are discussed. This is followed by an overview of several estimation methods proposed in literature, which has been applied to acceleration records from vehicle and earthquake induced vibrations. Additionally, basic techniques for processing and analysing (acceleration) signals are presented, which are required in the estimation procedures. Three of the proposed estimation methods are then chosen and described in detail. The chosen methods are applied to measured data from a steel box girder bridge located in Japan. The acceleration measurements were obtained during an experimental field measurement and during an earthquake, thus providing acceleration data from vehicle and earthquake induced vibrations, which are investigated separately. Displacement measurements were also conducted during the field measurement, providing the possibility of validation for the estimated values. In the final part, the results from the estimation are presented and discussed, as well as difficulties which have appeared during the calculations. The section concludes with an evaluation of the applicability of the methods and recommendations on possible further research topics in this field.Das fortschreitende Altern und die Verschlechterung des Zustands von Brücken aufgrund ihres Gebrauchs geben Anlass zum Bedenken ihrer strukturellen Sicherheit und Benutzbarkeit. Regelmäßige Inspektionen werden durchgeführt, um den aktuellen Zustand des Bauwerks zu beurteilen, obwohl bestimmte Arten von Schäden bei den primär per Augenschein durchgeführten Inspektionen schwierig zu erkennen sind. Um dieses Problem zu lösen, werden Überwachungssysteme eingesetzt, die aus verschiedenen Sensoren bestehen. Diese sind am Bauwerk angebracht und liefern zusätzliche Informationen, die als Entscheidungsgrundlage für geeignete Instandhaltungsmaßnahmen dienen. Das Überwachungssystem kann entweder dauerhaft angebracht sein, um unter täglichen Bedingungen zu arbeiten, oder gezielt während Inspektionen eingesetzt werden. Insbesondere bei Stahlbrücken ermöglicht das Wissen um das Verschiebungsverhalten das Erkennen dynamischer Verformungen, die zu lokalen Spannungskonzentrationen und folglich Ermüdungserscheinungen und Sprödbrüchen führen können. Die Verschiebungsantworten können entweder aus den Messungen von Verschiebungssensoren erhalten werden oder durch doppelte Integration der Beschleunigung, die von den Beschleunigungssensoren des Überwachungssystems gemessen werden, bestimmt werden. Da sich der erste Ansatz in der Anwendung als unpraktisch herausstellt, erscheint die Integration von Beschleunigungsaufzeichnungen zu den Verschiebungsantworten als die bessere Wahl. Die von Beschleunigungssensoren gemessenen Daten enthalten jedoch Messfehler, die sich bei zweimaliger Integration vergrößern und zu physisch unwahrscheinlichen Verschiebungsverläufen und Verzerrungen führen. Der Fokus dieser Arbeit liegt auf der Darstellung und Bewertung verschiedener Ansätze zur Beseitigung der Auswirkung von Messfehlern im Integrationsprozess, der Anwendung der ausgewählten Methoden auf Messdaten und der Bewertung ihrer Anwendbarkeit und der Genauigkeit der Ergebnisse. Im ersten Teil dieser Arbeit wird eine Einführung in das Überwachungssystem gegeben und die grundlegende Theorie sowie Schwierigkeiten im Integrationsverfahren werden diskutiert. Darauf folgt ein Überblick über mehrere Berechnungsverfahren, die in der Literatur für Beschleunigungsaufzeichnungen von Fahrzeug- und erdbebeninduzierten Vibrationen vorgeschlagen werden. Zusätzlich werden grundlegende Techniken zur Verarbeitung und Analyse von (Beschleunigungs-) Signalen vorgestellt, die in den Verfahren erforderlich sind. Drei der vorgeschlagenen Berechnungsverfahren werden dann ausgewählt und im Detail beschrieben. Die gewählten Methoden werden auf Messdaten einer Stahlkastenträgerbrücke in Japan angewendet. Die Beschleunigungsmessungen wurden während einer experimentellen Feldmessung und während eines Erdbebens durchgeführt und liefern so Beschleunigungsdaten von Fahrzeug- und Erdbeben-induzierten Vibrationen, die separat untersucht werden. Während der Feldmessung wurden auch Verschiebungsmessungen durchgeführt, welche die Validierung der berechneten bzw. abgeschätzten Werte ermöglichen. Im letzten Teil werden die Ergebnisse der Abschätzung präsentiert und diskutiert sowie die Schwierigkeiten, die während der Berechnungen aufgetreten sind. Der Abschnitt schließt mit einer Bewertung der Anwendbarkeit der Methoden und Empfehlungen zu möglichen weiteren Forschungsthemen auf diesem Gebiet
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
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