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41.
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   
42.
43.
This paper analyzes the compromise social choice correspondence derived from the τ-value of digraph games. Monotonicity of this correspondence is shown. A connection between several properties of social choice correspondences based on game theoretical solutions and game theoretical properties of the underlying solutions is given. Applications to several game theoretic solutions are provided.  相似文献   
44.
A technique is described for the measurement of all components of mean velocity and Reynolds stresses, in a complex turbulent flow where achieving coincidence data acquisition is difficult. The method is based on data recorded using four orientations of the laser probe. It is shown that the measurement errors are not the same for all the components of the Reynolds tensor, but they are sufficiently small to give a good accuracy. An application to a turbomachinery flow is given to illustrate the method.  相似文献   
45.
A novel super-hydrophobic stearic acid (STA) film with a water contact angle of 166o was prepared by chemical adsorption on aluminum wafer coated with polyethyleneimine (PEI) film. The micro-tribological behavior of the super-hydrophobic STA monolayer was compared with that of the polished and PEI-coated Al surfaces. The effect of relative humidity on the adhesion and friction was investigated as well. It was found that the STA monolayer showed decreased friction, while the adhesive force was greatly decreased by increasing the surface roughness of the Al wafer to reduce the contact area between the atomic force microscope (AFM) tip and the sample surface to be tested. Thus the friction and adhesion of the Al wafer was effectively decreased by generating the STA monolayer, which indicated that it could be feasible and rational to prepare a surface with good adhesion resistance and lubricity by properly controlling the surface morphology and the chemical composition. Both the adhesion and friction decreased as the relative humidity was lowered from 65% to 10%, though the decrease extent became insignificant for the STA monolayer. The project supported by the National Natural Science Foundation of China (50375151, 50323007, 10225209) and the Chinese Academy of Sciences (KJCX-SW-L2)  相似文献   
46.
We carried out detailed calculations for photorefractive wave-mixing switches based on one of three crystals with high electro-optic coefficients, namely, BaTiO3, Strontium Barium Niobate (SBN (0.75)), and Potasium Sodium Strontium Barium Niobate (KNSBN). A comparison of results for the three crystals shows that a 0_-cut BaTiO3 crystal is suitable for a longitudinal switch and requires a voltage of about 80 for a 2-mm-thick crystal to induce sufficient phase mismatch. The electrodes must be transparent for the incident and diffracted beams. A 45_-cut SBN (0.75) crystal, however, is suitable for a lateral switch and requires a voltage of about 150 for a 1-mm-wide crystal. The electrodes do not need to be transparent.  相似文献   
47.
We measured the entire region of mesopic and photopic vision to determine the color zone covering the visual field with unique red, yellow, green, and blue hue components. Eight kinds of test stimuli in the natural color system (NCS) color notation system were used. These stimuli were presented at horizontal and vertical meridians, and at meridians inclined at 45° angles. The illuminance level was set at six levels: 0.01 lx-1000 lx. The evaluation method measured chromatic, white, and black components as well as the hue component of the stimuli. Results show that the color zone of the retina extended further into the periphery with increasing illuminance; the response of opponent colors y-b was shown to be greater than that of the opponent colors r-g.  相似文献   
48.
A new optical technique based on real time holographic interferometry in true colors has been implemented around the transonic wind tunnel of the ONERA-Lille center to analyze 2D unsteady wake flows. Tests realized in color interferometry, real time and double exposure, use simultaneously three wavelengths of a continuous waves laser (argon and krypton mixed) and holograms are recorded on silver-halide single-layer panchromatic Slavich PFG03c plates. The very principle of real-time true color holographic interferometry uses three primary wavelengths (red, green and blue) to record, under no-flow conditions, the interference among the three measurement beams and the three reference beams simultaneously on a single reference hologram. After the holographic plate is developed, it is placed on the test setup again in the position it occupied during exposure and the hologram is illuminated again by the three reference beams and three measurement beams. A flat, uniform color can then be observed behind the hologram. So a horizontal, vertical, or even circular fringe pattern can be formed and the achromatic central fringe can be made out very clearly. The single color is used to determine the path difference zero on the interferograms. The flow studied was the unsteady flow downstream of a cylinder placed crosswise in the test section. A sequence of hundred interferograms was recorded on the flow around the cylinder at Mach 0.37. The vortex formation and dissipation phases can be seen very clearly, along with the fringe beat to either side of the cylinder.  相似文献   
49.
Two benzoyl substituted chitosan derivatives, 3,6‐O‐dibenzoylchitosan (DBC) and 2‐N‐3,6‐O‐tribenzoylchitosan (TBC), were prepared, and their optical activities in organic solvent were investigated by circular dichroism (CD). For TBC, two splitting bands (a negative one at 288 nm and a positive one at 274 nm) corresponding to the 1Lb transition of the benzoyl group were observed in chloroform and dichloromethane, while only a negative CD band was recorded in N, N‐dimethylformamide (DMF). These results indicated that the transition moments of benzoyl groups were orderly arranged along the helical polymer chain when TBC was dissolved in a solvent with low polarity, but the same ordered structure did not appear in a polar solvent of DMF. For DBC, only negative CD signals corresponding to the 1Lb transition of the benzoyl group were observed, regardless of the solvent property, which indicated that the chromophores were not arranged in an ordered fashion with appropriate geometry to interact with one another to induce bi‐signate CD signals. Adding methanol or DMF to the solution of TBC/chloroform resulted in a progressive decrease of the intensity of the positive split band at 274 nm. The intensity of the positive band was weakened upon heating a solution of TBC/chloroform from 20 to 60 °C. The results suggested that the ordered arrangement of the chromophores in the TBC system was dependent on solvent and sensitive to temperature. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4107–4115, 2004  相似文献   
50.
The electrode reaction of decamethylferrocene (DMFc) dissolved in a thin layer of a room-temperature molten salt (RTMS), 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (C8mimC1C1N) or 1-octyl-3-methylimidazolium bis(pentafluoroethylsulfonyl)imide (C8mimC2C2N), on a self-assembled monolayer-modified gold electrode is coupled with the ion transfer across the interface between the RTMS and the outer aqueous solution (W) to give a voltammogram whose shape resembles a voltammogram of a simple one-electron transfer process. The electroneutrality of the RTMS layer during the oxidation of DMFc to decamethylferricenium ion is maintained by the concomitant dissolution of C8mim+ ion from the RTMS phase to the W phase, and the reduction of decamethylferricenium ion to DMFc is accompanied by the transfer of either C1C1N- or C2C2N- from RTMS to W. The midpoint potential of the voltammogram varies with the concentration of the salt in the aqueous phase, C8mimCl or LiCnCnN (n = 1 or 2), in a Nernstian manner, showing that the phase-boundary potential between the RTMS and the W is controlled by the partition of these ions. Although the phase-boundary potential across the RTMS / W interface is Nernstian with respect to the ions common to both phases at the equilibrium, the polarization at the RTMS / W interface under current flow distorts the shape of the voltammograms, resulting in a wider peak separation in the voltammogram.  相似文献   
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