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91.
Andrej Ule 《Acta Analytica》2004,19(33):9-30
I analyze some classical solutions of the skeptical argument and some of their week points (especially the contextualist solution).
First I have proposed some possible improvement of the contextualist solution (the introduction of the explicit-implicit belief
and knowledge distinction beside the differences in the relevance of some counter-factual alternatives). However, this solution
does not block too fast jumps of the everyday context (where empirical knowledge is possible) into skeptical context (where
empirical knowledge is impossible). Then I analyze some formal analogies between some modal arguments on the contingency of
empirical facts (and the world as whole) and the skeptical arguments against empirical knowledge. I try to show that the skeptical
conclusion “Empirical knowledge does not exist” is logically coherent with the thesis that they are empirical facts and that
we have true belief on them. In order to do that without contradictions I have to accept a non-classical definition of knowledge:
S knows that p:= S is not justified to allow that non-p. Knowledge and justified allowance function here as some pseudo-theoretical
concepts which allow only some partial and conditional definitions by some “empirical” terms and logical conditions. 相似文献
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We formulate coordinate-free conditions for identifying all the symmetry classes of the elasticity tensor and prove that these conditions are both necessary and sufficient. Also, we construct a natural coordinate system of this tensor without the a priory knowledge of the symmetry axes. 相似文献
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Orinák A Arlinghaus HF Vering G Orináková R Hellweg S 《Journal of chromatography. A》2005,1084(1-2):113-118
New on-line analytical system coupling thin layer chromatography (TLC) and high selective identification unit-time of flight secondary ion mass spectrometry (TOF-SIMS) is introduced in this article. Chromatographic mixture separation and analyte surface deposition followed with surface TOF-SIMS analysis on-line allows to identify the analytes at trace and ultratrace levels. The selected analytes with different detectability and identification possibility were analysed in this hyphenated unit (Methyl Red indicator, Terpinolen and Giberrelic acid). Here, the chromatographic thin layer plays a universal role: separation unit, analyte depositing surface and TOF-SIMS interface, finally. Two depositing substrates and TOF-SIMS compatible interfaces were tested in above-mentioned interfacing unit: modified aluminium backed chromatographic thin layer and monolithic silica thin layer. The sets of positive and negative ions TOF-SIMS spectra obtained from different SIMS modes of analysis were used for analyte identification purposes. SIMS enables analyte detection with high mass resolution at the concentration level that is not achieved by other methods. 相似文献
96.
Pyrolysis-capillary gas chromatography (Py-cGC) represents important method to identify the analytes in the mixture after thermal degradation. This combines high effective analyte separation on-line coupled with thermal degradation process that depends on analyte structure. System of retention indices has been used for identification of the analytes after on-line pyrolysis and chromatographic separation. The pyrolysate composition has been studied during thermal degradation of polymethylmethacrylate (PMMA) at different pyrolysis temperatures and chromatographic column conditions. Homologues series of n-alkanes have been used for calculation of pyrolysate Kováts retention indices (I) and compared with mass spectrometric (MS) data of pyrolysate model mixture. To identify PMMA thermal degradation products the high density polyethylene (HDPE) as additive standard producing triplets of the olefin homologous series during co-pyrolysis has been used. These homologous series enable to calculate programmed temperature retention indices (ITPGC) to identify the analytes present in the pyrolysate. Calculated I values were compared with published I values databases to identify analytes yielded at different pyrolysis temperatures. 相似文献
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98.
Andrej Thurzo Viera Jan
ovi
ov Miroslav Hain Milan Thurzo Bohuslav Novk Helena Kosn
ov Viera Lehotsk Ivan Varga Peter Kov
Norbert Moravanský 《Molecules (Basel, Switzerland)》2022,27(13)
(1) Teeth, in humans, represent the most resilient tissues. However, exposure to concentrated acids might lead to their dissolving, thus making human identification difficult. Teeth often contain dental restorations from materials that are even more resilient to acid impact. This paper aims to introduce a novel method for the 3D reconstruction of dental patterns as a crucial step for the digital identification of dental records. (2) With a combination of modern methods, including micro-computed tomography, cone-beam computer tomography, and attenuated total reflection, in conjunction with Fourier transform infrared spectroscopy and artificial intelligence convolutional neural network algorithms, this paper presents a method for 3D-dental-pattern reconstruction, and human remains identification. Our research studies the morphology of teeth, bone, and dental materials (amalgam, composite, glass-ionomer cement) under different periods of exposure to 75% sulfuric acid. (3) Our results reveal a significant volume loss in bone, enamel, dentine, as well as glass-ionomer cement. The results also reveal a significant resistance by the composite and amalgam dental materials to the impact of sulfuric acid, thus serving as strong parts in the dental-pattern mosaic. This paper also probably introduces the first successful artificial intelligence application in automated-forensic-CBCT segmentation. (4) Interdisciplinary cooperation, utilizing the mentioned technologies, can solve the problem of human remains identification with a 3D reconstruction of dental patterns and their 2D projections over existing ante-mortem records. 相似文献
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