124,939 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Surface gravities for non-Killing horizons
No full textThere are many logically and computationally distinct characterizations of the surface gravity of a horizon, just as there are many logically rather distinct notions of horizon. Fortunately, in standard general relativity, for stationary horizons, these characterizations are degenerate. However, in modified gravity, or in analogue spacetimes, horizons may be non-Killing or even non-null, and hence these degeneracies can be lifted. We present a brief overview of the key issues, specifically focusing on horizons in analogue spacetimes and universal horizons in modified gravity
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
Analogue black holes in relativistic BECs: Mimicking Killing and universal horizons
No full textRelativistic Bose-Einstein condensates (rBECs) have recently become a
well-established system for analogue gravity. Indeed, while such
relativistic systems cannot be yet realized experimentally, they provide
an interesting framework for mimicking metrics for which no analogue is
yet available, thus paving the way for further theoretical and numerical
explorations. In this vein, we here discuss black holes in rBECs and
explore how their features relate to the bulk properties of the system.
We then propose the coupling of external fields to the rBEC as a way to
mimic nonmetric features. In particular, we use a Proca field to
simulate an aether field, as found in Einstein-aether or Ho.
rava-Lifshitz gravity. This allows us to mimic a universal horizon, the
causal barrier relevant for superluminal modes in these modified
gravitational theories
B&O Potato Club Sweepstakes Awarded at the 1933 Indiana State Fair
No full textMr. O.K. Quivey, agricultural agent for the Baltimore and Ohio Railroad, is seen here presenting a check to 10 year-old George Martin Cropp, son of Mr. and Mrs. G.M. Cropp, of Shoals, Indiana. The check was sweepstakes prize money for George's winning entry in the B&O Potato Club exhibit. Left to right: Quivey, Mr. Cropp, George Cropp, and Jesse Wood, the Martin County agent who encouraged George in his potato club work
Vorticity in analog gravity
No full textIn the analog gravity framework, the acoustic disturbances in a moving
fluid can be described by an equation of motion identical to a
relativistic scalar massless field propagating in curved space-time.
This description is possible only when the fluid under consideration is
barotropic, inviscid, and irrotational. In this case, the propagation of
the perturbations is governed by an acoustic metric that depends
algebrically on the local speed of sound, density, and the background
flow velocity, the latter assumed to be vorticity-free. In this work we
provide a straightforward extension in order to go beyond the
irrotational constraint. Using a charged-relativistic and
nonrelativistic-Bose- Einstein condensate as a physical system, we show
that in the low-momentum limit and performing the eikonal approximation
we can derive a d'Alembertian equation of motion for the charged phonons
where the emergent acoustic metric depends on flow velocity in the
presence of vorticity
Correction to: An eco-evolutionary system with naturally bounded traits
No full textCorrection to: Theoretical Ecology
https://doi.org/10.1007/s12080-019-0407-6
The original version of this article unfortunately contains an incorrect panel (b) in Fig. 1 introduced during the production process. The correct Fig. 1 is shown next page:
Ecospace diagrams illustrating the initial conditions (blue dots) and stable invasion outcomes (black dots) under ecological theory used for the four scenarios: a competitive exclusion—either x1 or x2 could survive depending on initial conditions, but for this initial condition x1 will survive and x2 will fail to invade; b competitive exclusion—R∗ theory predicts that x1 will win and x2 will go extinct; c competitive exclusion—R∗ theory predicts that x2 will win and x1 will go extinct; d competitive coexistence—both populations survive but x1 will dominate in non-adaptive scenarios. The lines are zero isoclines, the dots are stable (black) or unstable (white) equilibriums or initial conditions (blue). The vector field (blue arrows) show how the system changes in time. The initial population values have x1 set to its carrying capacity (i.e. x∗1=K1=r1/a11) and x∗2=0.05. Technically, R∗ is only relevant to panels b and c, but we will use the term generically to mean the outcome of non-evolutionary competition. (See Table 1 for parameter values)No Full Tex
Pragmatic Case Studies as a Source of Unity in Applied Psychology
No full textTo unify or not to unify applied psychology: that is the question. In this article we review pendulum swings in the historical efforts to answer this question—from a comprehensive, positivist, “top-down,” deductive yes between the 1930s and the early 60s, to a postmodern no since then. A rationale and proposal for a limited, “bottom-up,” inductive yes in applied psychology is then presented, employing a case-based paradigm that integrates both positivist and postmodern themes and components. This paradigm is labeled “pragmatic psychology” and, its specific use of case studies, the “Pragmatic Case Study Method” (“PCS Method”). We call for the creation of peer-reviewed journal-databases of pragmatic case studies as a foundational source of unifying applied knowledge in our discipline. As one example, the potential of the PCS Method for unifying different angles of theoretical regard is illustrated in an area of applied psychology, psychotherapy, via the case of Mrs. B. The article then turns to the broader historical and epistemological arguments for the unifying nature of the PCS Method in both applied and basic psychology.Peer reviewe
Dr. Edwin Wright Collection: Author Unknown
No full textNotes - The author relates several short stories about his neighbours including Alex McDonell, homesteading and life around Meanook and Athabasca (1 page
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
- …
