1,721,023 research outputs found
Investigation of E-Turbo Fuel Consumption Reduction Implications on Passenger Car Applications
No full textOne of the main challenges related to the development of modern propulsion systems
for light duty vehicles is the reduction of CO2 emissions, which may be
achieved through different approaches. If we consider the Spark Ignition (SI) Internal
Combustion Engine (ICE), relatively high efficient solutions have been recently developed
by drastically reducing engine displacement, while at the same time guaranteeing
adequate driving performance by adding turbocharging systems and/or additional
energy storage and propulsion systems (hybrid powertrains. [1]). Exhaust energy
waste is certainly another extremely interesting area for increasing the overall
efficiency of the powertrain [2-4], and it should be recalled that the combination of
exhaust gas turbocharging with energy recovery through turbo machines is a wellestablished
technology for large engines (turbo-compound [3, 7, 8, 9]), while it is recently
being considered also for highly downsized engines, due to more frequent operation
at high load [6].
This paper investigates a possible approach for extreme CO2 reduction, consisting
of an E-turbo concept (a reversible electrical machine mechanically coupled to an
exhaust gas turbocharger) applied to a “small” 1.4 liter SI engine. The hybridization
technology that has been considered in this study is similar to the F1 2014 ERS (Energy
Recovery System) system, but the main focus is on fuel consumption reduction
evaluation when considering a passenger car application. The simulation analysis
has been carried out by defining a reference, fully validated, turbo-charged engine
model, and by subsequently investigating required turbine boundary conditions
(mainly backpressure and efficiency), both for a Waste Gate (WG) and a Variable
Geometry Turbine (VGT) solution. This preliminary analysis allowed the definition of
a suitable turbocharger matching for the E-turbo configuration, and the capability of
analyzing particularly interesting phenomena, such as part load lower bounds (limits
of energy recovery definition), achievable level of downsizing and downspeeding (by
investigating different transmission ratios), and the transient response of the E-Turbo
system.
This simulation environment will be used in the next steps of the project [11] to evaluate
the effects of E-turbo concepts (and related downsizing/downspeeding benefits)
on fuel consumption, when considering homologation cycle scenarios. Another area
to be deeply investigated is the definition of the electric machine performance requirements
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
A Point Process Framework for the Characterization of Fetal Sleep States
No full textIn the fetal period, the progressive coordination among several subsystems promotes the emergence of sleep states. For this reason, the characterization of fetal behavioral states plays a crucial role in assessing fetal wellbeing. Nevertheless, current methodologies aimed at assessing fetal sleep states over limited time intervals require visual observation of the traces. In this work, we validate a point process approach for a continuous in time characterization of fetal behavioral states. We compare traditional heart rate variability (HRV) parameters and the corresponding point process-extracted sets of time and frequency measures in a population of 39 fetuses whose fetal ECG was recorded overnight during the third trimester of gestation.Clinical Relevance - Our results provide evidence for the proposed point process framework to capture fetal HRV dynamics with a high degree of reliability, suggesting its potential application for instantaneous estimates of fetal sleep states
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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