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Veicoli ricreativi progettati per l'utente quotidiano
Full text linkThe present work summarizes the results of the design, and development of design methods for vehicles, mainly two wheeled.
Part I. Design of the tilting chassis for a three wheels vehicle for mid-range mobility. The vehicle, equipped by electric assistance, thus can achieve reasonable speed. To avoid the overturning in curve an innovative tilt system, developed by the research group, was implemented and optimized by means of multibody dynamics simulation. Part II. The market of enduro motorcycles offers no vehicles specifically designed for the needs of non-professional users, therefore was developed a motorcycle designed for handling rather than performance. The early definition of design objectives different from the traditional ones led the development of a controlled stiffness chassis, and an engine characterized by reduced gyroscopic effects. Part III. The need to objectively measure and quantify the behavior of the motorcycle driver out of the laboratory is now urgent in applied research. Only few attempts have been made, mainly because of cost and technical difficulties. The use of techniques of emph image processing allowed the development of a noncontact measurement system, using a single emph action camera to reconstruct the movements of the pilot in six degrees of freedom. Part IV. Laser cutting of tubes provides technological potential not fully exploited in vehicle frame construction. Techniques have been developed of design for rapid assembly, and structural optimization of tubular structures.
The implementation is immediate within prototyping, while the research acts as foreground for industrial application.
Prototypes. Collaboration with industry yielded to the construction of prototypes in all projects, consequently have been studied some themes essentials for the complete design of the vehicles. Having dealt with transversal themes allowed to operate a profitable technological transfer between the areas addresse
Identification of the characteristics of motorcycle and scooter tyres in the presence of large variations in inflation pressure
No full textStability and safety of road vehicles are largely affected by tyre properties. Single-track vehicles are
characterised by weakly damped modes of vibration (weave and wobble) and therefore this phenomenon
is even more important. This article focuses on the study of both steady-state and transient
properties of motorcycle and scooter tyres in the presence of very low and very high inflation pressures.
The steady-state properties are defined as lateral forces (side-slip and camber forces) and yaw
torques (self-aligning and twisting). The transient properties are described in terms of relaxation
length, which represents the distance needed to reach a certain percentage of the steady-state value
of the tyre force. Experimental tests are carried out on a specific rotating disk machine. Three sets
of tyres are analysed. Steady-state properties are measured by increasing step by step the values of
camber and side-slip angles. Transient properties are studied carrying out tests with harmonic sideslip
excitation and measuring the phase lag between the excitation (input) and the tyre force (output).
Experimental results show important variations in tyre properties with inflation pressure with general
trends of all the tested tyres and particular features related to the tyre’s geometry. After the analysis
and discussion of experimental results, the measured data are fitted by means of a specific version
of the Magic Formula. The dependence of the Magic Formula’s coefficients on inflation pressure is
analysed and interpolation curves are given
Design of a hybrid propulsion system for a three wheeled bicycle
No full textPurpose – Velomobiles or bicycles cars are human-powered vehicles, enclosed for improving
aerodynamic performance and protection from weather and collisions. The purpose of this paper is to
design and develop a three-wheeled velomobile equipped with a hybrid human-electric propulsion
system.
Design/methodology/approach – The mechanical layout has been developed in order to improve
safety, a CAD code has been used for the design and the dynamic performances have been studied by
means of specific multi-body codes. The electric propulsion system has been designed both with
analytical and FEM methods.
Findings – A special three-wheeled tilting vehicle layout equipped with a four-bar linkage connection
has been developed. A particular synchronous reluctance machine has been developed, which is very
suitable for human-electric hybrid propulsion. A MATLAB code for integrated mechanical and
electrical analysis has been developed.
Originality/value – A new kind of light vehicle has been conceived. A new synchronous reluctance
machine with high efficiency has been developed. A performance analysis in electric, human and
hybrid working modes has been presented, which takes into account the specific features of both the
electric motor and the pedaling legs. A prototype of the vehicle has been built.
Keywords Dynamics, FEM, Electrical machines, Computer aided modelin
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
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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