1,721,195 research outputs found
Supply and Demand Analysis of a Free Floating Bike Sharing System
Full text linkThis article presents an analysis of the supply and demand of a FFBSS recently implemented in the city of Bologna, Italy. The main aspects treated in this paper are: analysis of bike availability; temporal analysis of FFBSS demand; calibration and validation of a novel model that predicts the number of daily trips per available bike. This model is based on a linear combination of several day attributes, including meteorological and day-type attributes. Moreover, an origin to destination analysis is generated showing the spatial distribution of FFBSS trips. The methods are applied to a scenario with almost a million GPS traces recorded between July and October 2018 by the FFBSS in Bologna. Findings could support FFBSS companies to better understand the fluctuation of both the transport demand and supply of this relatively recent transport mode, as to make more efficient decisions when distributing or relocating bicycles
Analysing the dynamic performances of a bicycle network with a temporal analysis of GPS traces
No full textThe main goal of this paper is to describe temporal analysis methods of cyclists’ GPS traces and apply them to a dataset recorded in the city of Bologna, Italy. The dataset consists of approximately 27,000 GPS bike traces registered in May 2016. The novelty of the developed method consists in a particular pre-processing step to reconstruction of the cyclist's speed profile, despite the disturbed location information of GPS traces. Thanks to a detailed representation of the road network, important indicators, such as speed in motion, average waiting times at intersections and even waiting times for specific turn manoeuvres inside junctions can be extracted from the speed profile. These are relevant quantities for the network analyses and the calibration of route choice models. The results reveal that waiting times represent 15% of the total trip duration in average and they differ significantly between cyclists and turn-typology, just as average speeds vary strongly among cyclists. These findings suggest that link-cost functions for bicycle routing should include both waiting times that could be modelled as a function of specific attributes of the network, as well as components that consider the different dynamic behavior of cyclists’ types (careful, correct, reckless)
Large-scale activity-based demand generation modeling: A literature review and exploration of potential approaches
Full text linkLarge-scale, activity-based microscopic transport models provide a powerful framework for analyzing dynamic travel demand and assessing the impact of transportation policies on daily travel behavior. At the core of these models is the generation of travel demand, which necessitates the creation of detailed synthetic populations and daily travel plans associated with personalized activities. These time-dependent travel plans are then integrated into dynamic traffic assignment models to simulate agent-based systems. This paper presents a comprehensive review of existing demand generation models within activity-based frameworks, focusing on various methodologies including constraint-based, utility-based, rule-based, learning-based, and hybrid approaches. A comparative analysis is offered, highlighting their theoretical foundations, data requirements, key outputs, and particularly their applications in large-scale microsimulations. In addition, the paper discusses the possibility of collecting input data for these models, as well as explores innovative approaches capable of modeling daily mobility patterns as sequences of activities linked by trips, offering greater flexibility in capturing dynamic travel behavior. Furthermore,potential research directions are also discussed, including the development of travel models for large-scale scenarios using big data sources and the optimization of their integration with dynamic traffic assignment. These methods hold significant promise for integration into large-scale, microscopic dynamic traffic assignment platforms. This study provides critical insights for researchers and practitioners focused on advancing large-scale microscopic traffic modeling to improve decision-making processes
Le grand atlas de l'archéologie. Réalisé sous la direction de J. Bersani, H. Schweizer, J. Gall, M. Lardy, Chr. Flon
No full textRaepsaet Georges. Le grand atlas de l'archéologie. Réalisé sous la direction de J. Bersani, H. Schweizer, J. Gall, M. Lardy, Chr. Flon. In: Revue belge de philologie et d'histoire, tome 67, fasc. 1, 1989. Antiquité - Oudheid. p. 224
Le grand atlas de l'archéologie. Réalisé sous la direction de J. Bersani, H. Schweizer, J. Gall, M. Lardy, Chr. Flon
No full textRaepsaet Georges. Le grand atlas de l'archéologie. Réalisé sous la direction de J. Bersani, H. Schweizer, J. Gall, M. Lardy, Chr. Flon. In: Revue belge de philologie et d'histoire, tome 67, fasc. 1, 1989. Antiquité - Oudheid. p. 224
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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