1,721,043 research outputs found
Characterisation of PZT thin film micro-actuators using a silicon micro-force sensor
Full text linkThis paper reports on the measurements of displacement and blocking force of piezoelectric micro-cantilevers. The free displacement was studied using a surface profiler and a laser vibrometer. The experimental data were compared with an analytical model which showed that the PZT thin film has a Young's modulus of 110 GPa and a piezoelectric coefficient d31,f of 30 pC/N. The blocking force was investigated by means of a micro-machined silicon force sensor based on the silicon piezoresistive effect. The generated force was detected by measuring a change in voltage within a piezoresistors bridge. The sensor was calibrated using a commercial nano-indenter as a force and displacement standard. Application of the method showed that a 700 μm long micro-cantilever showed a maximum displacement of 800 nm and a blocking force of 0.1 mN at an actuation voltage of 5 V, within experimental error of the theoretical predictions based on the known piezoelectric and elastic properties of the PZT film
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
Nanostructured bottom electrodes for ferroelectric thin films
No full textLead zirconate titanate
(PZT) is a oxide, which posseses a perovskite type structure.
The material is ferroelectric
making it technically useful for a diverse range of
applications from thermal imaging to non-volatile integrated memory devices. Thin
films of PZT are
commonly deposited onto platinised-silicon (Pt(111)/Ti/SíOX/Si)
bottom electrodes
by chemical solution deposition (CSD). Depending on the
conditions used a transient intermetallic
phase Pt3Pb can form in-situ with a (111)
preferred orientation during processing, which reduces the lattice mismatch between
the desired
perovskite phase and bottom electrode. Thereby, making it easier for the
perovskite phase to both nucleate and take on a preferred (111) orientation.
In the work
presented experiments were conducted on modifying the surface of
platinised-silicon to achieve a better lattice-match to Pb(Zr0_3Ti0_7)O3 (PZT30/70)
through coating, alloying or reacting the platinum with silver (Ag), gold (Au) or lead
(Pb). Single layer and multi-layer PZT thin fihns were deposited by a CSD method
onto these modified bottom electrodes and
plain platinised-silicon. Two precursor
sols were used one that had 10% excess Pb added
(PZT30/70) and one that had no
excess Pb added
(StoichPZT30/70). In general, two drying regimes prior to
crystallisation were employed for the precursor fihns.
i. Dried at 200°C for 3min
ii. Dried at 300°C for 5min
Crystallisation of the dried films was conducted i general at 480°C.
The
primary result of the work, showed that the presence of a lattice-matched
surface is
highly beneficial for nucleation of perovskite PZT and the subsequent
transformation from
amorphous precursor into perovskite PZT at low crystallisation
temperatures <500°C. All the modified bottom electrodes performed well when used
i
conjunction with fihns dried at 300°C for 5min, which otherwise would not
transform on plain platinised-silicon.
It was found that the Au and
Ag modified platinised-silicon behaved i a similar
manner to
plain platinised-silicon with respect to in-situ Pt3Pb, except that the Ag
modified
platinised-silicon appeared to impede its formation and promote its
oxidation. I
general the perovskite phase was detected by x-ray diffraction earlier
on
Ag modified platinised-silicon than on either Au modified or plain platinisedsilicon.
The
PZT30/70 thin films dried at 200°C for 3min on Au and
Ag modified
Abstract
bottom electrodes
appeared to have a higher crystallinity than similar than similar
films
deposited onto plain platinised-silicon. This was not observed for the
StoichPZT30/70 sol as the crystallinity of these films, dried at 200°C for 3mjn were
similar i value with all being greater than comparable PZT30/70 sol thin films.
It was also
proposed that the transformation rate from pyrochlore to perovskite
could be affected
by precursor sol Pb content and its distribution within the film
during crystallisation. This was illustrated when bottom electrodes containing Pt3Pb
before the film
deposition (ex-situ) were used. PZT30/70 films dried at 200°C for
3min, provide conditions for forming in-situ Pt3Pb and this produced poor quality
perovskite PZT thin films on ex-situ Pt3Pb. Implying that i the concentration of Pb is
too
high at the film/electrode, not only is the preferred orientation of the perovskite
thin film
compromised but also the degree of transformation from an amorphous to
the
perovskite phase will be compromised. However, StoichPZT30/70 films dried at
300°C for 5min do not form in-situ Pt3Pb on
crystallisation but When crystallised on
ex-situ Pt3Pb
they appear to transform rapidly into the perovskite phase with a
preferred (111) orientation
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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