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101.
Mylan Engel 《Acta Analytica》2005,20(2):56-79
The paper takes as its starting point the observation that people can be led to retract knowledge claims when presented with
previously ignored error possibilities, but offers a noncontextualist explanation of the data. Fallibilist epistemologies
are committed to the existence of two kinds of Kp-falsifying contingencies: (i) Non-Ignorable contingencies [NI-contingencies] and (ii) Properly-Ignorable contingencies [PI-contingencies]. For S to know that p, S must be in an epistemic position to rule out all NI-contingencies, but she need not be able to rule out the PI-contingencies.
What is required vis-à-vis PI-contingencies is that they all be false. In mentioning PI-contingencies, an interlocutor can lead S mistakenly to think that these contingencies are NI-contingencies, when in fact they are not. Since S cannot rule out these newly mentioned contingencies and since she mistakenly takes them to be NI-contingencies, it is quite natural that she retract her earlier knowledge claim. In short, mentioning NI-contingencies creates a distortion
effect. It makes S think that the standards for knowledge are higher than they actually are, which in turn explains why she mistakenly thinks
she lacks knowledge. Conclusion: The primary linguistic data offered in support of contextualism can be explained without
resorting to contextualism. 相似文献
102.
Atom diffraction from surfaces has proved to be a very useful method for structural studies on surfaces, particularly for incommensurate layers and hydrogen adlayers which are not easily analyzed with LEED. We have developed a rapid method to obtain the surface corrugation function directly from the measured intensities within the hard wall model. This avoids a tedious search in parameter space to determine surface structures and is valid for surfaces whose corrugation amplitudes are below the Rayleigh limit. We will discuss the method and its sensitivity to experimental errors in determining the diffraction intensities as well as its applicability when only a fraction of the allowed diffraction beams are experimentally accessible. 相似文献
103.
P. Merz R. Grieser G. Huber S. Karpuk V. Sebastian P. Seelig M. Grieser R. Grimm I. Lauer V. Luger D. Schwalm A. Dax T. Engel M. Gerlach T. Kühl H. Winter 《Hyperfine Interactions》1998,115(1-4):53-56
A preparation scheme for a 7Li+ ion beam in a storage ring is presented which provides ions in the metastable triplet states
with well controlled longitudinal phase space properties. For both state selective preparation and beam cooling, laser- and
electron-cooler forces are applied. The spatial- and momentum distributions of the ions are directly detected by a time resolved
measurement of the fluorescence light. At low beam intensities, the remaining heating rate of such a beam is completely determined
by residual gas scattering.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
104.
105.
Gernot M. Engel 《Linear algebra and its applications》1973,7(3):243-274
Using expansions of generalized matrix functions by means of cyclic products and principal majors, conditions for regularity of equimodular classes of matrices are found. 相似文献
106.
107.
Radial moments of the real part of the optical potential for elastic scattering of 104 MeV α particles are used as constraints, in determining the nuclear density of maximal entropy. The potential is related to the density by the folding model. 相似文献
108.
109.
Structure Elucidation of a Dimethylfulvene-trimer. Evidence for a [6+ 4]-Dimerization of 6, 6-Dimethylfulvene Thermal reaction of pure 6, 6-dimethylfulvene ( 1c ) at 60° gives an oligomeric mixture consisting mainly of fulvene-trimers. The structure of the main product 3c is partially elucidated by 1H-NMR. investigations at 400 MHz and definitely confirmed by X-ray analysis. The formation of 3c is explained in terms of a [6+4] dimerization, followed by a 1, 5-proton-shift and a final Diels-Alder reaction. 相似文献
110.
Measurements of the temperature dependence of e11 and e14 of α-quartz relative to room temperature based on thichkness mode resonances and antiresonances show that e14 changes its sign at ≈360°C. Fair agreement of e11 with values reported in earlier work was found. 相似文献