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41.
Computer Vision is a discipline whose ultimate goal is to interpret optical images of real scenes. It is well understood that such a problem is cursed by ambiguity of interpretation and uncertainty of evidence. Despite imperfectness of results due to the scenes never following our prior models exactly, Computer Vision has achieved a significant progress in the past two decades. This talk will outline the quest of 3D Computer Vision by describing a processing pipeline that receives a heap of unorganized images from unknown cameras and produces a consistent 3D geometric model together with camera calibrations. We will see how new algorithms allow the standard conception of the pipeline as a series of independent processing steps gradually transform to a single complex, yet efficient vision task. We will identify some points where linking Computer Vision and Computer Graphics would bring significant progress.  相似文献   
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The [2+2+2] cyclotrimerization of 1,7,9,15‐hexadecatetrayne with nitriles catalyzed by dicarbonylcyclopentadienylcobalt(I) opened a new pathway for the synthesis of C2‐symmetrical bis(tetrahydroisoquinolines) that were used as starting material for the preparation of axially chiral bipyridine N,N′‐dioxides. The N,N′‐dioxides (1 mol%) were found to be highly catalytically active and enantioselective (up to 83% ee) for the asymmetric allylation of aldehydes with allyl(trichloro)silane in various solvents. In addition, a dramatic solvent effect was observed where the use of different solvents induced opposite chiralities of the product with the same enantiomer of the catalyst, e.g., 65% ee (S) in acetonitrile (MeCN) vs. 82% ee (R) in chlorobenzene.  相似文献   
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We present new results on a recently developed method of factor analysis of data with ordinal attributes. The method is based on the apparatus of logic, the theory of relations and ordered sets, and provides an alternative to traditional methods of factor analysis. It utilizes formal concepts as factors and we demonstrate on several examples using sports data that the factors produced by the method are reasonable and easy-to-interpret. In addition, we propose ways to address various natural questions regarding the method and its use and put forward new research issues.  相似文献   
45.

We study interior operators from the point of view of fuzzy set theory. The present approach generalizes the particular cases studied previously in the literature in two aspects. First, we use complete residuated lattices as structures of truth values thus generalizing several important cases like the classical Boolean case, (left-)continuous t-norms, MV-algebras, BL-algebras, etc. Second, and more importantly, we pay attention to graded subsethood of fuzzy sets, which turns out to play an important role. In the first part, we define, illustrate by examples and study general fuzzy interior operators. The second part is devoted to fuzzy interior operators induced by fuzzy equivalence relations (similarities).  相似文献   
46.
The effect of electron-donor (piperidino) and electron-acceptor (cyano) groups on the absorption maxima of some diketo-pyrrolo-pyrroles in DMSO solution was investigated both experimentally and theoretically. The syntheses of push–pull substituted 3-(4-piperidinophenyl)-6-(4-cyanophenyl)-2,5-dihydropyrrolo[3,4-c]pyrrol-1,4-dione are reported for the first time; 3,6-diphenyl-2,5-dihydropyrrolo[3,4-c]pyrrol-1,4-diones substituted with either one or two piperidino or cyano groups in the para-positions of the phenyl rings were also synthesized. Whilst both types of substituent produce a bathochromic and hyperchromic shifts with respect to the parent unsubstituted compound, the influence of the piperidino group is strongest. Symmetrically substituted derivatives show well-resolved vibronic structures, while the spectra of polar, unsymmetrical compounds were poorly resolved because of strong dipole–dipole interaction with the polar solvent. The fluorescence of all compounds was intense and a significant increase in the Stokes shift of polar derivatives was another consequence of dipole–dipole interactions with the solvent in the excited state.  相似文献   
47.
BACKGROUND: Fusarium toxins, secondary metabolites of toxinogenic Fusarium species, are found in a range of cereal grains. In this study the occurrence of the most commonest Fusarium toxins, namely nivalenol (NIV), deoxynivalenol (DON), deoxynivalenol‐3‐glucoside, fusarenon‐X, 3‐ and 15‐acetyldeoxynivalenol, HT‐2 and T‐2 toxins and zearalenone, in various barley cultivars harvested in 2005–2008 was monitored. The impact of weather, locality, fungicide treatment and barley cultivar (hulless or covered) on contamination was evaluated. The transfer of these mycotoxins into malt was assessed. RESULTS: The most prevalent toxin was DON, which was found in 83% of samples (maximum level 180 µg kg?1), while HT‐2 was detected in 62% of samples (maximum level 716 µg kg?1). Using analysis of covariance, weather was found to be the key factor in all years (P < 0.001). A relationship between cultivar and contamination was confirmed only for HT‐2 (P < 0.001) and T‐2 (P = 0.037), with higher levels of these toxins being observed in hulless cultivars. With the exception of NIV (P = 0.008), no significant relationship was found between fungicide treatment and contamination. No distinct trend regarding DON levels in malt was found, with both decreases and increases occurring. CONCLUSION: The results show an inter‐annual variation in mycotoxin occurrence in barley cultivars as well as differences in contamination of malt produced from fungicide‐treated and untreated barley. Copyright © 2010 Society of Chemical Industry  相似文献   
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Abstract

Electronic charges, q, at nitrogen atoms of twelve m-dinitrobezopolyazaarenes were calculated by means of ab initio HF/6–31G?? and semi-empirical AM1 methods. The relationships have been confirmed between squares of the detonation velocities or, as the case may be, the detonation heats of the azaarenes and q-values for primarily split off nitro groups. These relationships were considered as an analogue of modified Evans-Polanyi-Semenov equation and so they directly specify the most reactive nitro groups of m-dinitrobenzopolyazaarene molecules in the detonation.  相似文献   
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