305,918 research outputs found
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
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
Experimental and methodic progress in ultra-small-angle polarised neutron scattering on novel magnetic materials
No full textUltra-small-angle scattering of polarised neutrons (USANSPOL) allows for the study of magnetic structure in the micrometre range [1]. The technique takes advantage from the narrow angular width of the Bragg reflection curve of perfect crystals and is employed in a double-crystal configuration of channel-cut perfect silicon crystals. Polarisation of the neutron beam is obtained by placing magnetic prisms, which act as birefringent regions, between the monochromator and analyser crystal [2]. Samples are placed between the polariser prisms and the analyser crystal. Scattering of spin-up and spin-down neutrons is recorded in a single measurement and identified by an angular shift of their respective scattering curves [3]. We have developed a prototype sample environment and handling system by which anisotropic samples may be aligned in different orientations and be subjected to external magnetic fields and stresses. Here, we present new experimental results on iron-boron ribbons of varying composition with remarkable magnetostriction properties, highly promising for technological application, and methodic development.
[1] G. Badurek, E. Jericha, R. Grössinger, R. Sato-Turtelli, J. Phys.: Conf. Ser. 211 (2010) 012027.
[2] E. Jericha, G. Badurek, M. Trinker, Physica B 397 (2007) 88.
[3] E. Jericha, G. Badurek, R. Grössinger, doi:10.1016/j.physb.2010.11.036
Ultra-small-angle polarised neutron scattering experiments on novel magnetic materials
No full textUltra-small-angle scattering of polarised neutrons (USANSPOL) allows for the study of magnetic structure in the micrometre range [1]. The technique takes advantage from the narrow angular width of the Bragg reflection curve of perfect crystals and is employed in a double-crystal configuration of channel-cut perfect silicon crystals. Polarisation of the neutron beam is obtained by placing magnetic prisms, which act as birefringent regions, between the monochromator and analyser crystal [2]. Samples are placed between the polariser prisms and the analyser crystal. Scattering of spin-up and spin-down neutrons is recorded in a single measurement and identified by an angular shift of their respective scattering curves [3]. We have developed a prototype sample environment and handling system by which anisotropic samples may be aligned in different orientations and be subjected to external magnetic fields and stresses. Here, we present experimental results on magnetic ribbons of varying composition with remarkable magnetostriction properties, highly promising for technological application, and methodic development. The potential of the USANSPOL technique is highlighted.
[1] G. Badurek, E. Jericha, R. Grössinger, R. Sato-Turtelli, J. Phys.: Conf. Ser. 211 (2010) 012027.
[2] E. Jericha, G. Badurek, M. Trinker, Physica B 397 (2007) 88.
[3] E. Jericha, G. Badurek, R. Grössinger, doi:10.1016/j.physb.2010.11.036
Author, publisher and bookseller : a tripartite synergy in Nigerian book industry
Full text linkThis work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
Ultra-small-angle polarized neutron scattering (USANSPOL)
No full textUltra-small-angle scattering of polarised neutrons (USANSPOL) allows for the study of magnetic structure in condensed matter in the micrometre range [1]. This technique takes advantage from the narrow angular width of the Bragg reflection by perfect crystals and is employed in a double-crystal configuration of perfect silicon crystals. Angular-correlated polarisation of the neutron beam is obtained by placing magnetic prisms between the monochromator and the analyser crystal [2]. Then, samples are placed between the polariser prisms and the analyser crystal. The scattering of spin-up and spin-down neutrons is recorded in a single measurement and identified by an angular shift of their respective scattering curves [3].
We have developed a special sample environment and handling system by which anisotropic samples may be aligned in different orientations and be subjected to varying external magnetic fields and mechanical stresses [4,5]. Here, we present experimental results on a variety of magnetic ribbons which represent both novel technologically relevant complex materials which are currently developed for use as magnetic sensors and actuators as well as illustrative examples for methodic development of the USANSPOL technique.
Experiments were carried out under various environmental conditions, including zero-field environment, the influence of external magnetic field, mechanically induced stress, or a combination of both effects, and in magnetically saturated state. Corresponding measurement results allow us to assess the native sample state and thereby also to characterise the manufacturing process which may create form anisotropies. Recording of the scattered neutron intensity under different sample orientations is essential for non-isotropic structures [5]. The evolution of the magnetic structure from this starting point is seen from experiments with applied external magnetic field and/or mechanical stress of varying strength and can be followed up to the angular resolution limit of the technique which corresponds to structure sizes of the order of a few ten micrometres. At the upper end of the internal length scale, we observe the sample under saturation conditions from which we may distinguish crystalline and amorphous states on a microstructure level with considerable implications on the applicability of the materials under investigation.
[1] G. Badurek, E. Jericha, R. Grössinger, R. Sato Turtelli, J. Phys.: Conf. Ser. 211, 2010, 012027.
[2] E. Jericha, G. Badurek, M. Trinker, Physica B 397, 2007, 88.
[3] E. Jericha, G. Badurek, R. Grössinger, Physica B 406, 2011, 2401.
[4] E. Jericha, G. Badurek, Ch. Gösselsberger, D. Süss, J. Phys.: Conf. Ser. 340, 2012, 012007.
[5] E. Jericha, G. Badurek, Ch. Gösselsberger, Physics Procedia 42, 2013, 58
[Report to Chief J. E. Curry, by an unknown author #2]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
[Report to Chief J. E. Curry, by an unknown author #1]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
MONOPOL - An ultra-flexible resonator for the tailoring of polarised neutron beams
No full textWe present a novel type of neutron spin resonator for precise wavelength selection and definition of the time structure of thermal, cold and even very cold polarised neutron beams [1]. This device exploits the fact that upon passage of neutrons through a spatially alternating transverse static magnetic field each neutron in its rest frame experiences an alternating field with a frequency depending on the neutron velocity and the spatial period of the resonator. If this frequency equals the Larmor precession frequency a resonant spin flip will take place [2]. Furthermore, the tailoring of the time structure of this neutron beam is completely decoupled from the adjustment of the wavelength resolution and allows for almost arbitrarily shaped neutron pulses by purely electronic means.
To demonstrate the feasibility of this technique, we designed and engineered two prototypes consisting of individually ultra-fast switchable aluminum stages for the generation of neutron pulses in the microsecond regime [3]. These resonators were installed at a polarised neutron beamline at the 250 kW TRIGA reactor of the Vienna University of Technology. Driven by the promising results of these test measure¬ments, a new resonator, for the application at very cold neutron (VCN) beamlines, has been developed. Here, we present results which demonstrate the successful operation of this device [4].
These developments are connected to the PERC project which searches for new physics beyond the Standard Model of particle physics via the beta-decay of free neutrons [2]. The related high precision measurements demand perfect knowledge of the key beam parameters, like wavelength distribution, degree of polarisation and time structure. Another direction is the implementation of our device as integrated monochromator and chopper for advanced neutron time-of-flight spectroscopy. In this context a novel Ramsey-type setup was introduced and experimentally tested [5].
[1] G. Badurek, E. Jericha, Physica B 335, 2003, 215.
[2] Ch. Gösselsberger, H. Abele, G. Badurek, E. Jericha, S. Nowak, G. Wautischer, A. Welzl, Physics Procedia 17, 2011, 62.
[3] G. Badurek, Ch. Gösselsberger, E. Jericha, Physica B 406, 2011, 2458.
[4] Ch. Gösselsberger, H. Abele, G. Badurek, E. Jericha, W. Mach, S. Nowak, T. Rechberger, J. Phys.: Conf. Ser. 340, 2012, 012028.
[5] Ch. Gösselsberger, M. Bacak, T. Gerstmayr, S. Gumpenberger, A. Hawlik, B. Hinterleitner, E. Jericha, S. Nowak, A. Welzl, G. Badurek, Physics Procedia 42, 2013, 106
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