In this paper, we address the problem of egomotion estimation for a monocular moving observer, under arbitrary translation and rotation. The method we propose is uniquely based on the spatio-temporal image derivatives, and has O(n 2) complexity. The approach consists in searching the image for particular geometric properties of the normal ow. The algorithm is performed in two successive steps: ...

[2+2+2] Cycloadditions can be applied to specifically build up derivatives of benzene and cyclohexadiene and, therefore, have attracted much attention. Herein, we present an intramolecular [2+2+2] cycloaddition of triynes catalyzed by the first-generation Grubbs ruthenium complex (Ru gen-1), which can efficiently afford benzene derivatives in good yields under mild conditions. Moreover, we also...

A double-wall-hourglass-shaped metallocavitand bearing an electron-deficient cavity was self-assembled, which exhibited an unusual selectivity to substituted benzene derivatives of different electron density during co-crystallizations.

We devise a statistical framework for edge detection by performing a statistical analysis of zero crossings of the second derivative of an image. This analysis enables us to estimate at each pixel of an image the probability that an edge passes through the pixel. We present a statistical analysis of the Lindeberg operators that we use to compute image derivatives. We also introduce a confidence...

A new two-dimensional (2D) carbon crystal, different from graphene, has been prepared from 1,3,5-trihydroxybenzene, consisting of 4-carbon and 6-carbon rings in 1:1 ratio, named 4-6 carbophene by authors, in which all carbon atoms possess sp2 hybrid orbitals with some distortion, forming an extensive conjugated π-bonding planar structure. The angles between the three σ-bonds of the carbon sp2 o...

a spectrophotometric method is used to determine the acidity constants of some derivatives of 9,10-anthraquinone in binary methanol-water mixtures at 25 °c. there is a linear inverse relationship between pka of all acids and the mole fraction of methanol in the mixed solvent. the influence of substituents in the molecular structure on the ionization constants is discussed.

quercetin, a ubiquitous flavonol, represents a promising leading drug for development of new chemotherapeutic agents. however, its limited cytotoxicity to cancer cells hampers its clinical use. in order to obtain novel quercetin derivatives with superior cytotoxicity, seven alkylated quercetin derivatives were synthesized. solubility of these derivatives was determined by turbidimetry. cytotoxi...

a series of new hexahydroquinoline and 1,4-dihydropyrimidine derivatives were synthesized. condensation of 2-methyl- thiazole-4-carboxaldehyde (1) with 1,3-cyclohexanedione and alkyl 3- aminocrotonate afforded 4-(2-methyl-thiazol-4-yl)-hexahydroquinoline while condensation of aldehyde (1) with benzoyl acetone and thiourea gave 1,4-dihydropyrimidine derivatives. the stereochemistry of 1,4-dihydr...