1,721,474 research outputs found
Scholz, C.: Strategische Organisation. Landsberg/Lech: Verlag Moderne Industrie, 1997
No full textBecker FG. Scholz, C.: Strategische Organisation. Landsberg/Lech: Verlag Moderne Industrie, 1997. Schmalenbachs Zeitschrift für betriebswirtschaftliche Forschung. 1999;51(11):1093-1095
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
Frictional behavior and constitutive modeling of simulated fault gouge
No full textPresents an investigation of the frictional properties and stability of frictional sliding for simulated fault gouge. In these experiments gouge layers (quartz sand) were sheared under saturated drained conditions and at constant normal stress (50-190 MPa) between either rough steel surfaces or Westerly granite surfaces in a triaxial apparatus. Porosity φ was monitored continuously during shear. Measurements indicate that granular gouge exhibits strain hardening and net compaction for shear strains γ >0.5-1.0. For γ sliding occurs at approximately constant shear stress and net compaction from one load/unload cycle to the next ceases. Dilatancy occurs at 1/3 to 1/2 the shear stress required for sliding and d2φ/dγ2 becomes negative at about the peak stress in a given loading cycle, indicating the onset of shear localization. Experiments with an initial gouge layer exhibit velocity strengthening, and initially bare granite surfaces exhibit velocity weakening. Data suggest that slip within unconsolidated granular material, such as some natural fault gouges, is inherently stable. -from Author
Particle-size distribution and microstructures within simulated fault gouge
No full textThis paper presents an investigation of comminution mechanisms and microstructure development within simulated fault gouge. We sheared 4.0 mm thick layers of quartz sand between rough steel surfaces using a triaxial apparatus. The layers were sheared at constant effective normal stress of 100 MPa, under saturated drained conditions, and at 45° to the axis of cylindrical steel samples. Porosity changes were measured throughout shear and microstructural observations were carried out on the deformed layers. Two types of load paths were investigated for shear strains (γ) between 0 and 3.3; either the shear stress was repeatedly cycled from zero to failure or the sample was sheared in a single-load cycle. Multiple-cycle experiments exhibit significantly more compaction than single-cycle experiments deformed to similar strains. Gouge layers from both sets of experiments contain oblique zones of localized shear (Riedel shears bands) after γ = 1.3-1.5. Gouge particles obey a fractal size distribution for the range 12.5-800μm; i.e. particle density vs size follows a power law, N(n)IA = bn-D where N(n) is the number of particles in a size range, A is the area examined, n is the mean of the size range, b is a constant and D is the fractal dimension. D for particles within the bulk material increases with shear strain for γ < about 1.5 after which it remains 2.6 ± 0.15. This value of D agrees with that found for natural fault gouge and with that predicted by a comminution model in which fracture probability depends on the relative size of nearest-neighbor particles. Analyses of particles within shear bands indicate continued size reduction after γ = 1.5. These particles do not obey a fractal size distribution for the range 6.25-100 μm due to a lack of particles larger than 25-50 μm. The rate of comminution within the bulk layer decreases at about γ = 1.5, which coincides with the onset of shear localization. Our data indicate that comminution is driven by relative movement between particles and that gouge layers attain a steady state particle-size distribution at γ = 1.5. The porosity-strain data and microstructural observations show a correlation between the onset of shear localization and the rate of dilatancy with shear strain. © 1989
The depth of seismic faulting and the upper transition from stable to unstable slip regimes
No full textA number of observations indicate that an upper stability transition occurs along well‐developed faults, such as the San Andreas, as a result of unconsolidated gouge within shallow regions of these faults. These observations include the depth distribution of seismicity along faults with and without well‐developed gouge zones, correlations between seismicity and shallow crustal structure, and modeling of coseismic and post‐seismic slip. In addition, recent experimental friction studies indicate that thick layers of simulated gouge exhibit a positive slip‐rate dependence of frictional resistance (velocity strengthening) and thus inherently stable slip, whereas bare rock surfaces and thin gouge layers exhibit potentially unstable velocity weakening behavior. Subduction zones with large accretionary wedges also exhibit an upper stability transition in that slip is aseismic within the accretionary wedge. A stability transition due to the presence of unconsolidated material can also be invoked in this case. Copyright 1988 by the American Geophysical Union
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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