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1.
Howard Robinson 《Acta Analytica》2005,20(3):7-10
Nicholas Nathan tries to resist the current version of the causal argument for sense-data in two ways. First he suggests that,
on what he considers to be the correct re-construction of the argument, it equivocates on the sense of proximate cause. Second
he defends a form of disjunctivism, by claiming that there might be an extra mechanism involved in producing veridical hallucination,
that is not present in perception. I argue that Nathan’s reconstruction of the argument is not the appropriate one, and that,
properly interpreted, the argument does not equivocate on proximate cause. Furthermore, I claim that his postulation of a
modified mechanism for hallucinations is implausibly ad hoc. 相似文献
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Howard Jacobowitz Gerardo Mendoza 《Transactions of the American Mathematical Society》2003,355(10):4201-4222
We study embeddings of complex vector bundles, especially line bundles, in the complexification of the tangent bundle of a manifold. The aim is to understand implications of properties of interest in partial differential equations.
5.
Paul Howard 《Mathematical Logic Quarterly》2007,53(3):247-254
Two theorems are proved: First that the statement “there exists a field F such that for every vector space over F, every generating set contains a basis” implies the axiom of choice. This generalizes theorems of Halpern, Blass, and Keremedis. Secondly, we prove that the assertion that every vector space over ?2 has a basis implies that every well‐ordered collection of two‐element sets has a choice function. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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7.
Summary. We examine the convergence characteristics of iterative methods based on a new preconditioning operator for solving the linear
systems arising from discretization and linearization of the steady-state Navier-Stokes equations. With a combination of analytic
and empirical results, we study the effects of fundamental parameters on convergence. We demonstrate that the preconditioned
problem has an eigenvalue distribution consisting of a tightly clustered set together with a small number of outliers. The
structure of these distributions is independent of the discretization mesh size, but the cardinality of the set of outliers
increases slowly as the viscosity becomes smaller. These characteristics are directly correlated with the convergence properties
of iterative solvers.
Received August 5, 2000 / Published online June 20, 2001 相似文献
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9.
A. S. Howard 《Physics of Atomic Nuclei》2004,67(11):2032-2040
The current status of direct dark matter searches by the Boulby Dark Matter Collaboration is presented with the latest result from the ZePLiN I liquid xenon detector. An upper limit in the interaction cross section per nucleon of ~1×10?6 pb for a WIMP mass of 100 GeV is found. Details of ZePLiN’s II and III—two future liquid xenon dark matter are presented. Extensive two-phase liquid-gas xenon prototype work has been undertaken and results of characterization studies are presented. The detector response to internal alpha and external gamma and neutron sources is shown. The potential discrimination power of the two-phase technique is displayed. Finally, prospects for the future dark matter search program are discussed. 相似文献
10.
K. D. Duch M. Heel H. Kalinowsky F. Kayser E. Klempt B. May O. Schreiber P. Weidenauer M. Ziegler D. Bailey S. Barlag J. M. Butler U. Gastaldi R. Landua C. Sabev W. Dahme F. Feld-Dahme U. Schaefer W. R. Wodrich J. C. Bizot B. Delcourt J. Jeanjean H. Nguyen E. G. Auld D. A. Axen K. L. Erdman B. Howard R. Howard B. L. White S. Ahmad M. Comyn G. M. Marshall G. Beer L. P. Robertson M. Botlo C. Laa H. Vonach C. Amsler M. Doser J. Riedlberger U. Straumann P. Truöl ASTERIX Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,45(2):223-234
Antiproton-proton annihilation at rest in a gaseous H2 target at NTP into the final state π+ π? K ± π? (K 0) with an undetectedK 0 or \(\bar K^0 \) has been investigated. We observe theE(1420) resonance in the invariant mass spectrum (K 0)miss K ± π? with massM E =1413±8 MeV/c2 and widthГ E =62 ± 16MeV/c2 and find evidence for the production of thef 1(1285). The absolute branching ratio of \(\bar p\) p → π+ π? E 0,E 0 →K 0 L K ± π ? at (61±6)%P wave annihilation is (3.0±0.9)·10?4 of all annihilations. The observed suppression of theE production fromP wave with respect to theS wave together with some simple selection rules suggest that the quantum numbers of theE(1420) areJ pc=0?+ and not I++. 相似文献