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111.
It is shown that the set of all multi-homography matrices describing I-element families of interdependent homographies between two views has dimension 4I + 7. 相似文献
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Three types of cross-linked porous organic polymers (either oxygen-, nitrogen-, or sulfur-doped) were carbonized under a chlorine atmosphere to obtain chars in the form of microporous heteroatom-doped carbons. The studied organic polymers constitute thermosetting resins obtained via sol-gel polycondensation of resorcinol and five-membered heterocyclic aldehydes (either furan, pyrrole, or thiophene). Carbonization under highly oxidative chlorine (concentrated and diluted Cl2 atmosphere) was compared with pyrolysis under an inert helium atmosphere. All pyrolyzed samples were additionally annealed under NH3. The influence of pyrolysis and additional annealing conditions on the carbon materials’ porosity and chemical composition was elucidated. 相似文献
117.
This paper deals with a class of controlled mechanical systems in which the number of control inputs, equal to the number
of desired system outputs, is smaller than the number of degrees of freedom. The related inverse dynamics control problem,
i.e., the determination of control input strategy that force the underactuated system to complete the partly specified motion,
is a challenging task. In the present formulation, the desired system outputs, expressed in terms of the system states, are
treated as servo-constraints on the system, and the problem is viewed from the constrained motion perspective. Mixed orthogonal-tangent
realization of the constraints by the available control reactions is stated, and a specialized methodology for solving the
“singular” control problem is developed. The governing equations are manipulated to index three differential-algebraic equations,
and a simple numerical code for solving the equations is proposed. The feedforward control law obtained as a solution to these
equations can then be enhanced by a closed-loop control strategy with feedback of the actual servo-constraint violations to
provide stable tracking of the reference motion in the presence of perturbations and modeling uncertainties. An overhead trolley
crane executing a load-prescribed motion serves as an illustration. Some results of numerical simulations are reported. 相似文献
118.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
119.
Wojciech Marynowski Tomasz Klucznik Katarzyna Baranowska Anna Dołęga Dr. Wiesław Wojnowski 《无机化学与普通化学杂志》2010,636(5):685-687
Tri(mesityloxy)silanethiol (TMST) was isolated as the only product of the reaction between SiS2 and 2,4,6‐trimethylphenol. TMST crystallizes in the triclinic system. Good quality of the crystal allowed the unrestricted refinement of the mercapto group; the resulting S–H distance is 1.29(4) Å and the Si–S–H bond angle is 95.4(17)°. Molecules of TMST show no hydrogen bonds in the crystal – the FT‐IR spectrum of the solid sample exhibits a very sharp, well‐resolved band of isolated –SH group at 2562 cm–1. 相似文献