177,233 research outputs found
Philosophical perspectives on ad hoc-hypotheses and the Higgs mechanism
No full textWe examine physicists' charge of adhocness against the Higgs mechanism in the Standard Model of elementary particle physics. We argue that even though this charge never rested on a clear-cut and well-entrenched definition of "ad hoc", it is based on conceptual and methodological assumptions and principles which are well-founded elements of the scientific practice of high-energy particle physics. Based on our findings, we dispute the claim made by Christopher Hunt in a recent article in "Philosophy of Science" that the use of "ad hoc" by scientists reflects nothing more substantial than a judgment made on the basis of their "individual aesthetic senses". We further evaluate the implications of the recent discovery of a Higgs-like particle at the CERN Large Hadron Collider for the charge of adhocness against the Higgs mechanism
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
The ∑3-conjecture For Metabelian Groups
No full textThe ∑3-conjecture for metabelian groups is proved in the split extension case.673609625Åberg, H., Bieri-Strebel valuations (of finite rank) (1986) Proc. London Math. Soc. (3), 52, pp. 269-304Bieri, R., Homological dimension of discrete groups, 2nd edn (1981) Queen Mary College Mathematics Notes, , Queen Mary College, LondonBieri, R., Geoohegan, R., Kernels of actions on non-positively curved spaces (1998) London Mathematical Society Lecture Note Series, 252, pp. 24-38. , Geometry and cohomology in group theory (Durham, 1994), Cambridge University Press, CambridgeBieri, R., Geoghegan, R., Connectivity Properties of Group Actions on Non-positively Curved Spaces. I: Controlled Connectivity and Openness Results, , preprintBieri, R., Geoghegan, R., Connectivity Properties of Group Actions on Non-positively Curved Spaces. II: The Geometric Invariants, , preprintBieri, R., Groves, J.R.J., Metabelian groups of type FP∞ are virtually of type FP (1982) Proc. London Math. Soc. (3), 45, pp. 365-384Bieri, R., Groves, J.R.J., The geometry of the set of characters induced by valuations (1984) J. Reine Angew. Math., 347, pp. 168-195Bieri, R., Harlander, J., On the FP3-conjecture for metabelian groups (2001) J. London Math. Soc. (2), 64, pp. 595-610Bieri, R., Harlander, J., A remark on the polyhedrality theorem for the ∑-invariants of modules over abelian groups (2001) Math. Proc. Cambridge Philos. Soc., 131, pp. 39-43Bieri, R., Renz, B., Valuations on free resolutions and higher geometric invariants of groups (1988) Comment. Math. Helv., 63, pp. 464-497Bieri, R., Strebel, R., Valuations and finitely presented metabelian groups (1980) Proc. London Math. Soc. (3), 41, pp. 439-464Bieri, R., Neumann, W.D., Strebel, R., A geometric invariant for discrete groups (1987) Invent. Math., 90, pp. 451-477Bux, K.U., Finiteness properties of certain metabelian arithmetic groups in the function field case (1997) Proc. London Math. Soc. (3), 75, pp. 308-322Harlander, J., Kochloukova, D.H., The ∑2-conjecture: The general case J. Algebra, , to appearKochloukova, D.H., The FPm-conjecture for a class of metabelian groups (1996) J. Algebra, 184, pp. 1175-1204Kochloukova, D.H., (1997) The FPm-Conjecture for a Class of Metabelian Groups, , PhD Thesis, University of CambridgeKochloukova, D.H., The ∑2-conjecture for metabelian groups and some new conjectures: The split extension case (1999) J. Algebra, 222, pp. 357-375Kochloukova, D.H., The ∑m-conjecture for a class of metabelian groups (1999) London Mathematical Society Lecture Note Series, 261, pp. 492-503. , Groups, St Andrews, Bath, 1997 (Cambridge University Press)Kochloukova, D.H., More about the geometric invariants ∑m(G) and ∑m(G,ℤ) for groups with normal locally polycyclic-by-finite subgroups (2001) Math. Proc. Cambridge Philos. Soc., 130, pp. 295-306Meinert, H., The homological invariants for metabelian groups of finite Prüfer rank: A proof of the ∑m-conjecture (1996) Proc. London Math. Soc., 72, pp. 385-424Meinert, H., Actions on 2-complexes and the homotopical invariant ∑2 of a group (1997) J. Pure Appl. Algebra, 119, pp. 297-317Noskov, G.A., The Bieri-Strebel invariant and homological finiteness conditions for metabelian groups (1997) Algebra i Logika, 36, pp. 194-21
Measurements of small radius ratio turbulent Taylor-Couette flow
No full textIn Taylor-Couette flow, the radius ratio () is one of the key parameters of the system. For small , the asymmetry of the inner and outer boundary layer becomes more important, affecting the general flow structure and boundary layer characteristics. Using high-resolution particle image velocimetry we measure flow profiles for a radius ratio of 0.5 and Taylor number of up to . By measuring at varying heights, roll structures are characterized for two different rotation ratios of the inner and outer cylinder. In addition, we investigate how the turbulent bursts coming from the inner and outer cylinder affect the flow profiles. These results exemplify how curvature affects flow in strongly turbulent Taylor-Couette Flow
The ∑2-conjecture For Metabelian Groups: The General Case
No full textThe Bieri-Neumann-Strebel invariant ∑m (G) of a group G is a certain subset of a sphere that contains information about finiteness properties of subgroups of G. In case of a metabelian group G the set ∑1 (G) completely characterizes finite presentability and it is conjectured that it also contains complete information about the higher finiteness properties (FPm-conjecture). The ∑m-conjecture states how the higher invariants are obtained from ∑1 (G). In this paper we prove the ∑2-conjecture. © 2004 Elsevier Inc. All rights reserved.2732435454Åberg, H., Bieri-Strebel valuations (of finite rank) (1986) Proc. London Math. Soc., 52 (3), pp. 269-304Bestvina, M., Brady, N., Morse theory and finiteness properties of groups (1997) Invent. Math., 129 (3), pp. 445-470Bieri, R., Groves, J.R.J., Metabelian groups of type FP∞ are virtually of type FP (1982) Proc. London Math. Soc., 45 (3), pp. 365-384Bieri, R., Groves, J.R.J., The geometry of the set of characters induced by valuations (1984) J. Reine Angew. Math., 347, pp. 168-195Bieri, R., Harlander, J., On the FP3-conjecture for metabelian groups (2001) J. London Math. Soc., 64 (2), pp. 595-610Bieri, R., Harlander, J., A remark on the polyhedrality theorem for the ∑-invariants of modules over abelian groups (2001) Math. Proc. Cambridge Philos. Soc., 131, pp. 39-43Bieri, R., Neumann, W.D., Strebel, R., A geometric invariant of discrete groups (1987) Invent. Math., 90, pp. 451-477Bieri, R., Renz, B., Valuations on free resolutions and higher geometric invariants of groups (1988) Comment. Math. Helv., 63, pp. 464-497Bieri, R., Strebel, R., Valuations and finitely presented metabelian groups (1980) Proc. London Math. Soc., 41 (3), pp. 439-464Brown, K.S., Cohomology of Groups (1982) Grad. Texts in Math., 87. , Springer-Verlag, New YorkBux, K.U., Finiteness properties of certain metabelian arithmetic groups in the function field case (1997) Proc. London Math. Soc., 75 (2), pp. 308-322Groves, J.R.J., Some finitely presented nilpotent-by-abelian groups (1991) J. Algebra, 144, pp. 127-166Gehrke, R., The higher geometric invariants for groups with sufficient commutativity (1998) Comm. Algebra, 26 (4), pp. 1097-1115Kochloukova, D.H., The ∑m-conjecture for a class of metabelian groups (1999) London Math. Soc. Lecture Note Ser., 261, pp. 492-503. , Groups St Andrews '97 in Bath, Cambridge Univ. Press, CambridgeKochloukova, D.H., The ∑2-conjecture for metabelian groups and some new conjectures: The split extension case (1999) J. Algebra, 222, pp. 357-375Kochloukova, D.H., The FPm-conjecture for a class of metabelian groups (1996) J. Algebra, 184, pp. 1175-1204Kochloukova, D.H., More about the geometric invariants ∑m (G) and ∑m (G, ℤ) for groups with normal locally polycyclic-by-finite subgroups (2001) Math. Proc. Cambridge Philos. Soc., 130 (2), pp. 295-306Kochloukova, D.H., Subgroups of constructible nilpotent-by-abelian groups and a generalization of a result of Bieri-Newmann-Strebel (2002) J. Group Theory, 5, pp. 219-231Meinert, H., Actions on 2-complexes and the homotopical invariant ∑2 of a group (1997) J. Pure Appl. Algebra, 119 (3), pp. 297-317Meinert, H., The homological invariants for metabelian groups of finite Prüfer rank: A proof of the ∑m-conjecture (1996) Proc. London Math. Soc., 72 (2), pp. 385-424Meier, J., Meinert, H., VanWyk, L., Higher generation subgroup sets and the ∑-invariants of graph groups (1998) Comment. Math. Helv., 73 (1), pp. 22-44Noskov, G.A., The Bieri-Strebel invariant and homological finiteness conditions for metabelian groups (1997) Algebra I Logika, 36 (2), pp. 194-218Renz, B., Geometrische Invarianten und Endlichkeitseigenschaften von Gruppen, Dissertation (1988), Universität Frankfurt a.
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
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
Letter from R. R. Zellick, Assistant Trust Officer, Anglo California National Bank of San Francisco, to Joseph R. Goodman, October 2, 1942
No full textLetter from R. R. Zellick, Assistant Trust Officer at The Anglo California National Bank of San Francisco, to Joseph R. Goodman, regarding property owned by Dave Tatsuno. Zellick mentions a dispute between current tenants and Tatsuno, and that Tatsuno has asked Goodman to help locate trustworthy tenants.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
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
Liftings for noncomplete probability spaces
No full textThe current state of knowledge concerning liftings for noncomplete probability spaces is discussed. This is a somewhat expanded version of the author's talk given at the 1991 Summer Conference on General Topology and Applications in Honor of Mary Ellen Rudin and Her Work.PT: S; CR: BURKE MR, IN PRESS P AM MATH S BURKE MR, 1991, ISRAEL J MATH, V73, P33 BURKE MR, 1992, ISRAEL J MATH, V79, P289 CARLSON T, THEOREM LIFTING CHRISTENSEN JPR, 1974, TOPOLOGY BOREL STRUC FREMLIN DH, 1989, HDB BOOLEAN ALGEBRAS, P877 INOESCUTULCEA A, 1966, 5TH P BERK S MATH ST, V2 IONESCUTULCEA A, 1967, CONTRIBUTIONS PROB 1, P63 IONESCUTULCEA A, 1969, TOPICS THEORY LIFTIN JECH TJ, 1978, SET THEORY JOHNSON RA, 1980, P AM MATH SOC, V80, P234 JUST W, IN PRESS T AM MATH S KUPKA J, 1983, INDIANA U MATH J, V32, P717 LOSERT V, 1983, LNM, V1080, P95 MAHARAM D, 1958, P AM MATH SOC, V9, P987 SHELAH S, 1983, ISRAEL J MATH, V45, P90 TALAGRAND M, 1982, P AM MATH SOC, V84, P379 VONNEUMANN J, 1931, CRELLES J MATH, V165, P109; NR: 18; TC: 0; J9: ANN N Y ACAD SCI; PG: 4; GA: BZ86BSource type: Electronic(1
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